Intervals

Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 5488    Accepted Submission(s): 1999

Problem Description
You are given n closed, integer intervals [ai, bi] and n integers c1, ..., cn.

Write a program that:

> reads the number of intervals, their endpoints and integers c1, ..., cn from the standard input,

> computes the minimal size of a set Z of integers which has at least ci common elements with interval [ai, bi], for each i = 1, 2, ..., n,

> writes the answer to the standard output

 
Input
The first line of the input contains an integer n (1 <= n <= 50 000) - the number of intervals. The following n lines describe the intervals. The i+1-th line of the input contains three integers ai, bi and ci separated by single spaces and such that 0 <= ai <= bi <= 50 000 and 1 <= ci <= bi - ai + 1.

Process to the end of file.

 
Output
The output contains exactly one integer equal to the minimal size of set Z sharing at least ci elements with interval [ai, bi], for each i = 1, 2, ..., n.
 
Sample Input
5
3 7 3
8 10 3
6 8 1
1 3 1
10 11 1
 
Sample Output
6
 
Author
1384
 
Recommend
Eddy
 
倒没想到隐含条件
做含有不等式关系的题时要想到差分约束
设sum(a) 为小于等于a的在集合中的元素
根据
如果需要求的是两个变量差的最大值,那么需要将所有不等式转变成"<="的形式,建图后求最短路;相反,如果需要求的是两个变量差的最小值,那么需要将所有不等式转化成">=",建图后求最长路
建图
注意隐含条件
sum(i) - sum(i - 1) >= 0
sum(i) - sum(i - 1) <= 1
 
#include <iostream>
#include <cstdio>
#include <sstream>
#include <cstring>
#include <map>
#include <cctype>
#include <set>
#include <vector>
#include <stack>
#include <queue>
#include <algorithm>
#include <cmath>
#include <bitset>
#define rap(i, a, n) for(int i=a; i<=n; i++)
#define rep(i, a, n) for(int i=a; i<n; i++)
#define lap(i, a, n) for(int i=n; i>=a; i--)
#define lep(i, a, n) for(int i=n; i>a; i--)
#define rd(a) scanf("%d", &a)
#define rlld(a) scanf("%lld", &a)
#define rc(a) scanf("%c", &a)
#define rs(a) scanf("%s", a)
#define rb(a) scanf("%lf", &a)
#define rf(a) scanf("%f", &a)
#define pd(a) printf("%d\n", a)
#define plld(a) printf("%lld\n", a)
#define pc(a) printf("%c\n", a)
#define ps(a) printf("%s\n", a)
#define MOD 2018
#define LL long long
#define ULL unsigned long long
#define Pair pair<int, int>
#define mem(a, b) memset(a, b, sizeof(a))
#define _ ios_base::sync_with_stdio(0),cin.tie(0)
//freopen("1.txt", "r", stdin);
using namespace std;
const int maxn = , INF = 0x7fffffff;
int head[maxn], nex[maxn << ], d[maxn], vis[maxn];
int cnt, n, ans[maxn];
struct node
{
int u, v, w;
}Node[maxn << ]; void add(int u, int v, int w)
{
Node[cnt].u = u;
Node[cnt].v = v;
Node[cnt].w = w;
nex[cnt] = head[u];
head[u] = cnt++;
} bool spfa(int s)
{
mem(d, -0x3f);
queue<int> Q;
Q.push(s);
vis[s] = ;
d[s] = ;
while(!Q.empty())
{
int u = Q.front(); Q.pop();
vis[u] = ;
for(int i = head[u]; i != -; i = nex[i])
{
int v = Node[i].v;
if(d[v] < d[u] + Node[i].w)
{
d[v] = d[u] + Node[i].w;
if(!vis[v])
{
Q.push(v);
vis[v] = ;
if(++ans[v] > n) return ;
}
}
}
}
return ;
} int main()
{ while(~scanf("%d", &n))
{
mem(head, -);
mem(vis, );
mem(ans, );
cnt = ;
int u, v, w;
int mx = -INF, mi = INF;
for(int i = ; i <= n; i++)
{
rd(u), rd(v), rd(w);
u++, v++;
mx = max(mx, v);
mi = min(mi, u);
add(u - , v, w);
}
for(int i = mi; i <= mx; i++)
{
// add(mi, i, 0);
add(i - , i, );
add(i, i - , -);
} spfa(mi - ); pd(d[mx]); } return ;
}

World Exhibition

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 2440    Accepted Submission(s): 1171

Problem Description
Nowadays, many people want to go to Shanghai to visit the World Exhibition. So there are always a lot of people who are standing along a straight line waiting for entering. Assume that there are N (2 <= N <= 1,000) people numbered 1..N who are standing in the same order as they are numbered. It is possible that two or more person line up at exactly the same location in the condition that those visit it in a group.

There is something interesting. Some like each other and want to be within a certain distance of each other in line. Some really dislike each other and want to be separated by at least a certain distance. A list of X (1 <= X <= 10,000) constraints describes which person like each other and the maximum distance by which they may be separated; a subsequent list of Y constraints (1 <= Y <= 10,000) tells which person dislike each other and the minimum distance by which they must be separated.

Your job is to compute, if possible, the maximum possible distance between person 1 and person N that satisfies the distance constraints.

 
Input
First line: An integer T represents the case of test.

The next line: Three space-separated integers: N, X, and Y.

The next X lines: Each line contains three space-separated positive integers: A, B, and C, with 1 <= A < B <= N. Person A and B must be at most C (1 <= C <= 1,000,000) apart.

The next Y lines: Each line contains three space-separated positive integers: A, B, and C, with 1 <= A < B <= C. Person A and B must be at least C (1 <= C <= 1,000,000) apart.

 
Output
For each line: A single integer. If no line-up is possible, output -1. If person 1 and N can be arbitrarily far apart, output -2. Otherwise output the greatest possible distance between person 1 and N.
 
Sample Input
1
4 2 1
1 3 8
2 4 15
2 3 4
 
Sample Output
19
 
Author
alpc20
 
Source
 
Recommend
zhouzeyong
 
#include <iostream>
#include <cstdio>
#include <sstream>
#include <cstring>
#include <map>
#include <set>
#include <vector>
#include <stack>
#include <queue>
#include <algorithm>
#include <cmath>
#define rap(i, a, n) for(int i=a; i<=n; i++)
#define MOD 2018
#define LL long long
#define ULL unsigned long long
#define Pair pair<int, int>
#define mem(a, b) memset(a, b, sizeof(a))
#define _ ios_base::sync_with_stdio(0),cin.tie(0)
//freopen("1.txt", "r", stdin);
using namespace std;
const int maxn = , INF = 0x7fffffff;
int head[maxn], ans[maxn], vis[maxn];
int n, m, cnt, s;
int d[maxn]; struct node
{
int v, next;
int w;
}Node[maxn*]; void add(int u, int v, int w)
{
Node[cnt].v = v;
Node[cnt].w = w;
Node[cnt].next = head[u];
head[u] = cnt++;
} int spfa()
{
// mem(vis, 0);
for(int i = ; i < maxn; i++) d[i] = INF;
queue<int> Q;
mem(ans, );
Q.push(s);
vis[s] = ;
d[s] = ;
// mem(vis, 0);
// for(int i=1; i<=n; i++)
// {
// Q.push(i);
// d[i] = INF;
// vis[i] = 1;
// }
while(!Q.empty())
{
int u = Q.front(); Q.pop();
vis[u] = ;
for(int i=head[u]; i!=-; i=Node[i].next)
{
node e = Node[i];
if(d[e.v] > d[u] + e.w)
{
d[e.v] = d[u] + e.w;
if(!vis[e.v])
{
Q.push(e.v);
vis[e.v] = ;
if(++ans[e.v] > n) return ;
}
}
}
}
return ;
} void init()
{
mem(head, -);
cnt = ;
} bool check(int x)
{
bool flag = ;
for(int i = ; i < cnt; i++)
Node[i].w -= x;
if(spfa())
flag = ;
for(int i = ; i < cnt; i++)
Node[i].w += x;
return flag;
} int main()
{
int x;
int T;
scanf("%d", &T);
while(T--)
{
scanf("%d%d%d", &n, &m, &x);
init();
int u, v, w, l = , r = ;
s = ;
rap(i, , m)
{
scanf("%d%d%d", &u, &v, &w);
if(u > v) swap(u, v);
add(u, v, w);
}
rap(i, , x)
{
scanf("%d%d%d", &u, &v, &w);
if(u > v) swap(u, v);
add(v, u, -w);
}
if(spfa()) printf("-1\n");
else if(d[n] == INF)
printf("-2\n");
else
printf("%d\n", d[n]); } return ;
}

King

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 2348    Accepted Submission(s): 1052

Problem Description
Once, in one kingdom, there was a queen and that queen was expecting a baby. The queen prayed: ``If my child was a son and if only he was a sound king.'' After nine months her child was born, and indeed, she gave birth to a nice son. 
Unfortunately, as it used to happen in royal families, the son was a little retarded. After many years of study he was able just to add integer numbers and to compare whether the result is greater or less than a given integer number. In addition, the numbers had to be written in a sequence and he was able to sum just continuous subsequences of the sequence.

The old king was very unhappy of his son. But he was ready to make everything to enable his son to govern the kingdom after his death. With regards to his son's skills he decided that every problem the king had to decide about had to be presented in a form of a finite sequence of integer numbers and the decision about it would be done by stating an integer constraint (i.e. an upper or lower limit) for the sum of that sequence. In this way there was at least some hope that his son would be able to make some decisions.

After the old king died, the young king began to reign. But very soon, a lot of people became very unsatisfied with his decisions and decided to dethrone him. They tried to do it by proving that his decisions were wrong.

Therefore some conspirators presented to the young king a set of problems that he had to decide about. The set of problems was in the form of subsequences Si = {aSi, aSi+1, ..., aSi+ni} of a sequence S = {a1, a2, ..., an}. The king thought a minute and then decided, i.e. he set for the sum aSi + aSi+1 + ... + aSi+ni of each subsequence Si an integer constraint ki (i.e. aSi + aSi+1 + ... + aSi+ni < ki or aSi + aSi+1 + ... + aSi+ni > ki resp.) and declared these constraints as his decisions.

After a while he realized that some of his decisions were wrong. He could not revoke the declared constraints but trying to save himself he decided to fake the sequence that he was given. He ordered to his advisors to find such a sequence S that would satisfy the constraints he set. Help the advisors of the king and write a program that decides whether such a sequence exists or not.

 
Input
The input consists of blocks of lines. Each block except the last corresponds to one set of problems and king's decisions about them. In the first line of the block there are integers n, and m where 0 < n <= 100 is length of the sequence S and 0 < m <= 100 is the number of subsequences Si. Next m lines contain particular decisions coded in the form of quadruples si, ni, oi, ki, where oi represents operator > (coded as gt) or operator < (coded as lt) respectively. The symbols si, ni and ki have the meaning described above. The last block consists of just one line containing 0.
 
Output
The output contains the lines corresponding to the blocks in the input. A line contains text successful conspiracy when such a sequence does not exist. Otherwise it contains text lamentable kingdom. There is no line in the output corresponding to the last ``null'' block of the input.
 
Sample Input
4 2
1 2 gt 0
2 2 lt 2
1 2
1 0 gt 0
1 0 lt 0
0
 
Sample Output
lamentable kingdom
successful conspiracy
 
Source
 
Recommend
LL
 
#include <iostream>
#include <cstdio>
#include <sstream>
#include <cstring>
#include <map>
#include <set>
#include <vector>
#include <stack>
#include <queue>
#include <algorithm>
#include <cmath>
#define rap(i, a, n) for(int i=a; i<=n; i++)
#define MOD 2018
#define LL long long
#define ULL unsigned long long
#define Pair pair<int, int>
#define mem(a, b) memset(a, b, sizeof(a))
#define _ ios_base::sync_with_stdio(0),cin.tie(0)
//freopen("1.txt", "r", stdin);
using namespace std;
const int maxn = , INF = 0x7fffffff;
int head[maxn], ans[maxn], vis[maxn];
int n, m, cnt, s;
int d[maxn]; struct node
{
int v, next;
int w;
}Node[maxn*]; void add(int u, int v, int w)
{
Node[cnt].v = v;
Node[cnt].w = w;
Node[cnt].next = head[u];
head[u] = cnt++;
} int spfa()
{
mem(vis, );
mem(d, 0x3f);
queue<int> Q;
mem(ans, ); for(int i=; i<=n; i++)
{
Q.push(i);
d[i] = ;
vis[i] = ;
}
while(!Q.empty())
{
int u = Q.front(); Q.pop();
vis[u] = ;
for(int i=head[u]; i!=-; i=Node[i].next)
{
node e = Node[i];
if(d[e.v] > d[u] + e.w)
{
d[e.v] = d[u] + e.w;
if(!vis[e.v])
{
Q.push(e.v);
vis[e.v] = ;
if(++ans[e.v] > n) return ;
}
}
}
}
return ;
} void init()
{
mem(head, -);
cnt = ;
} bool check(int x)
{
bool flag = ;
for(int i = ; i < cnt; i++)
Node[i].w -= x;
if(spfa())
flag = ;
for(int i = ; i < cnt; i++)
Node[i].w += x;
return flag;
} int main()
{
int x;
while(scanf("%d", &n) && n)
{
scanf("%d", &m);
init();
int u, v, w, l = , r = ;
s = n + ;
char str[];
rap(i, , m)
{
scanf("%d%d%s%d", &u, &v, str, &w);
if(str[] == 'g')
add(u - , u + v, - - w);
else
add(u + v, u - , w - );
} bool flag = spfa();
if(flag)
cout << "successful conspiracy" << endl;
else
cout << "lamentable kingdom" << endl; } return ;
}

THE MATRIX PROBLEM

Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 9774    Accepted Submission(s): 2508

Problem Description
You have been given a matrix CN*M, each element E of CN*M is positive and no more than 1000, The problem is that if there exist N numbers a1, a2, … an and M numbers b1, b2, …, bm, which satisfies that each elements in row-i multiplied with ai and each elements in column-j divided by bj, after this operation every element in this matrix is between L and U, L indicates the lowerbound and U indicates the upperbound of these elements.
 
Input
There are several test cases. You should process to the end of file.
Each case includes two parts, in part 1, there are four integers in one line, N,M,L,U, indicating the matrix has N rows and M columns, L is the lowerbound and U is the upperbound (1<=N、M<=400,1<=L<=U<=10000). In part 2, there are N lines, each line includes M integers, and they are the elements of the matrix.

 
Output
If there is a solution print "YES", else print "NO".
 
Sample Input
3 3 1 6
2 3 4
8 2 6
5 2 9
 
Sample Output
YES
 
Source
 
Recommend
lcy

可以得出要求是 L <= num[i][j] * a[i] / b[j] <= U

可以转换一下变成

log(L / num[i][j]) <= log(a[i]) - log(b[i]) <= log(U / num[i][j])

#include <iostream>
#include <cstdio>
#include <sstream>
#include <cstring>
#include <map>
#include <cctype>
#include <set>
#include <vector>
#include <stack>
#include <queue>
#include <algorithm>
#include <cmath>
#include <bitset>
#define rap(i, a, n) for(int i=a; i<=n; i++)
#define rep(i, a, n) for(int i=a; i<n; i++)
#define lap(i, a, n) for(int i=n; i>=a; i--)
#define lep(i, a, n) for(int i=n; i>a; i--)
#define rd(a) scanf("%d", &a)
#define rlld(a) scanf("%lld", &a)
#define rc(a) scanf("%c", &a)
#define rs(a) scanf("%s", a)
#define rb(a) scanf("%lf", &a)
#define rf(a) scanf("%f", &a)
#define pd(a) printf("%d\n", a)
#define plld(a) printf("%lld\n", a)
#define pc(a) printf("%c\n", a)
#define ps(a) printf("%s\n", a)
#define MOD 2018
#define LL long long
#define ULL unsigned long long
#define Pair pair<int, int>
#define mem(a, b) memset(a, b, sizeof(a))
#define _ ios_base::sync_with_stdio(0),cin.tie(0)
//freopen("1.txt", "r", stdin);
using namespace std;
const int maxn = , INF = 0x7fffffff;
int n, m, s;
int head[maxn], cnt, nex[maxn << ], vis[maxn];
int ans[maxn];
double d[maxn];
struct node
{
int u, v;
double w;
}Node[maxn << ]; void add(int u, int v, double w)
{
Node[cnt].u = u;
Node[cnt].v = v;
Node[cnt].w = w;
nex[cnt] = head[u];
head[u] = cnt++;
} int spfa()
{
for(int i = ; i < maxn; i++) d[i] = INF;
mem(ans, );
deque<int> Q;
Q.push_front(s);
mem(vis, );
vis[s] = ;
d[s] = ;
while(!Q.empty())
{
int u = Q.front(); Q.pop_front();
vis[u] = ;
for(int i = head[u]; i != -; i = nex[i])
{
int v = Node[i].v;
if(d[v] > d[u] + Node[i].w)
{
d[v] = d[u] + Node[i].w;
if(!vis[v])
{
if(Q.empty()) Q.push_front(v);
else if(d[v] < d[Q.front()]) Q.push_front(v);
else Q.push_back(v);
vis[v] = ;
if(++ans[v] > n) return ;
}
}
}
}
return ;
} int main()
{
int l, r;
while(scanf("%d%d%d%d", &n, &m, &l, &r) != EOF)
{
mem(head, -);
cnt = ;
int u, v, x;
s = ;
for(int i = ; i <= n; i++)
for(int j = ; j <= m; j ++)
{
rd(x);
add(i, n + j, -log(l / (double) x));
add(n + j, i, log(r / (double) x));
} if(spfa())
cout << "NO" << endl;
else cout << "YES" << endl; } return ;
}
 

差分约束 HDU - 1384 HDU - 3592 HDU - 1531 HDU - 3666的更多相关文章

  1. hdu 1531(差分约束)

    题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1531 差分约束的题之前也碰到过,刚好最近正在进行图论专题的训练,就拿来做一做. ①:对于差分不等式,a ...

  2. POJ 3169 Layout (HDU 3592) 差分约束

    http://poj.org/problem?id=3169 http://acm.hdu.edu.cn/showproblem.php?pid=3592 题目大意: 一些母牛按序号排成一条直线.有两 ...

  3. hdu 1384 Intervals (差分约束)

    Intervals Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total ...

  4. hdu 1384 Intervals (差分约束)

    Problem - 1384 好歹用了一天,也算是看懂了差分约束的原理,做出第一条查分约束了. 题意是告诉你一些区间中最少有多少元素,最少需要多少个元素才能满足所有要求. 构图的方法是,(a)-> ...

  5. HDU 1384 Intervals【差分约束-SPFA】

    类型:给出一些形如a−b<=k的不等式(或a−b>=k或a−b<k或a−b>k等),问是否有解[是否有负环]或求差的极值[最短/长路径].例子:b−a<=k1,c−b&l ...

  6. hdu 1531 king(差分约束)

    King Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submis ...

  7. POJ 1364 / HDU 3666 【差分约束-SPFA】

    POJ 1364 题解:最短路式子:d[v]<=d[u]+w 式子1:sum[a+b+1]−sum[a]>c      —      sum[a]<=sum[a+b+1]−c−1  ...

  8. hdu 1534 Schedule Problem (差分约束)

    Schedule Problem Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) ...

  9. I - 动物狂想曲 HDU - 6252(差分约束)

    I - 动物狂想曲 HDU - 6252 雷格西桑和路易桑是好朋友,在同一家公司工作.他们总是一起乘地铁去上班.他们的路线上有N个地铁站,编号从1到N.1站是他们的家,N站是公司. 有一天,雷格西桑起 ...

随机推荐

  1. OpenXMl倒出word、PDF

    OpenXMl倒出word.PDF @using MarkdownSharp @{     ViewBag.Title = "预览";     Layout = "~/V ...

  2. Linux基本命令操作

    3.1  Linux终端介绍.Shell提示符.Bash基本语法 3.1.1  登录LINUX终端 两种终端仿真器:1.GNOME桌面的GHOME Terminal : 2.KDE桌面的Konsole ...

  3. 六大设计原则(四)ISP接口隔离原则(上)

    ISP的定义 首先明确接口定义 实例接口 我们在Java中,一个类用New关键字来创建一个实例.抛开Java语言我们其实也可以称为接口.假设Person zhangsan = new Person() ...

  4. 008. 阻塞&非阻塞、同步&异步

    阻塞 非阻塞:关注的对象是调用者: 阻塞:调用者发起调用后,处于等待状态,直到该调用有返回: 非阻塞:调用者发起调用后,不需要等待返回,可以往下执行: 同步 异步:  关注的对象是被调用者: 同步:服 ...

  5. 常见的网页图像格式有 ico、jpg、png、gif,说说他们各自的应用场景

    1.ico:一般作为网页的标题上面的图标出现,文件 favicon.ico一般存放在网站根目录 2.jpg:非常适合作为储存像素色彩丰富的图片.例如照片等等 3.png:分为 png-8 以及 png ...

  6. Android为TV端助力:adb查找包名位置

    logcat | grep START 查找启动launcher adb shell "pm list packages -f | grep +包名" 查找包的路径

  7. Jenkins实现简单的CI功能

    步骤一:安装JDK.Tomcat,小儿科的东西不在此详细描述 步骤二:下载安装Jenkins下载链接:https://jenkins.io/download/ 步骤三:将下载的jenkins.war部 ...

  8. phpdocumentor 安装以及使用说明

    一  缘由 最近改版公司网站和app端的api,发现很多函数和方法都没写注释,搞得每次调用之前还需要看底层实现,有的方法名和功能还类似,区分不出使用哪个最优!为了避免给后人挖坑,除了将代码写得规范外, ...

  9. MySQL 是如何解决幻读的

    MySQL 是如何解决幻读的 一.什么是幻读 在一次事务里面,多次查询之后,结果集的个数不一致的情况叫做幻读. 而多出来或者少的哪一行被叫做 幻行 二.为什么要解决幻读 在高并发数据库系统中,需要保证 ...

  10. 码农也来关注下经济问题<美元加息>对我们的影响

    昨天凌晨三点,美联储宣布加息25个基点,这是今年美联储第四次加息,也是2015年12月份以来的第九次加息.基准利率又上调了25个基点,全球市场又要开始惴惴不安了. 要知道上一次美国基准利率上调25个基 ...