There are n cities numbered from 1 to n in Berland. Some of them are connected by two-way roads. Each road has its own length — an integer number from 1 to 1000. It is known that from each city it is possible to get to any other city by existing roads. Also for each pair of cities it is known the shortest distance between them. Berland Government plans to build k new roads. For each of the planned road it is known its length, and what cities it will connect. To control the correctness of the construction of new roads, after the opening of another road Berland government wants to check the sum of the shortest distances between all pairs of cities. Help them — for a given matrix of shortest distances on the old roads and plans of all new roads, find out how the sum of the shortest distances between all pairs of cities changes after construction of each road.

Input

The first line contains integer n (2 ≤ n ≤ 300) — amount of cities in Berland. Then there follow n lines with n integer numbers each — the matrix of shortest distances. j-th integer in the i-th row — di, j, the shortest distance between cities i and j. It is guaranteed that di, i = 0, di, j = dj, i, and a given matrix is a matrix of shortest distances for some set of two-way roads with integer lengths from 1 to 1000, such that from each city it is possible to get to any other city using these roads.

Next line contains integer k (1 ≤ k ≤ 300) — amount of planned roads. Following k lines contain the description of the planned roads. Each road is described by three space-separated integers aibici (1 ≤ ai, bi ≤ n, ai ≠ bi, 1 ≤ ci ≤ 1000) — ai and bi — pair of cities, which the road connects, ci — the length of the road. It can be several roads between a pair of cities, but no road connects the city with itself.

Output

Output k space-separated integers qi (1 ≤ i ≤ k). qi should be equal to the sum of shortest distances between all pairs of cities after the construction of roads with indexes from 1 to i. Roads are numbered from 1 in the input order. Each pair of cities should be taken into account in the sum exactly once, i. e. we count unordered pairs.

Examples

Input
2
0 5
5 0
1
1 2 3
Output
3 
Input
3
0 4 5
4 0 9
5 9 0
2
2 3 8
1 2 1
Output
17 12 

思路:要求每一对的最短路,直接想到floyd,但是每次都全跑一次一定会超时,那就每次把修改的边作为中间点进行floyd即可,代码如下:
#include<bits/stdc++.h>
using namespace std;
typedef long long LL; const int maxm = ; int G[maxm][maxm];
int N, K; void calculate() {
for(int k = ; k <= N; ++k)
for(int i = ; i <= N; ++i)
for(int j = ; j <= N; ++j)
G[i][j] = min(G[i][j], G[i][k] + G[k][j]);
} int main() {
scanf("%d", &N);
int t;
for(int i = ; i <= N; ++i)
for(int j = ; j <= N; ++j) {
scanf("%d", &G[i][j]);
}
calculate();
scanf("%d", &K);
int u, v;
for(int f = ; f < K; ++f) {
scanf("%d%d%d", &u, &v, &t);
LL ans = ;
if(t < G[u][v]) {
G[u][v] = G[v][u] = t;
for(int i = ; i <= N; ++i)
for(int j = ; j <= N; ++j) {
G[i][j] = min(G[i][j], min(G[i][u]+G[u][j], G[i][v]+G[v][j]));
G[j][i] = G[i][j];
}
}
for(int i = ; i < N; ++i)
for(int j = i+; j <= N; ++j)
ans += G[i][j];
printf("%I64d ", ans);
}
return ;
}

Day4 - M - Roads in Berland CodeForces - 25C的更多相关文章

  1. Codeforces Beta Round #25 (Div. 2 Only) C. Roads in Berland

    C. Roads in Berland time limit per test 2 seconds memory limit per test 256 megabytes input standard ...

  2. CodeForces 25C(Floyed 最短路)

    F - Roads in Berland Time Limit:2000MS     Memory Limit:262144KB     64bit IO Format:%I64d & %I6 ...

  3. 【Codeforces 25C】Roads in Berland

    [链接] 我是链接,点我呀:) [题意] 题意 [题解] 用floyd思想. 求出来这条新加的边影响到的点对即可. 然后尝试更新点对之间的最短路就好. 更新之后把差值从答案里面减掉. [代码] #in ...

  4. Roads in Berland(图论)

    Description There are n cities numbered from 1 to n in Berland. Some of them are connected by two-wa ...

  5. C. Roads in Berland

    题目链接: http://codeforces.com/problemset/problem/25/C 题意: 给一个最初的所有点与点之间的最短距离的矩阵.然后向图里加边,原有的边不变,问加边后的各个 ...

  6. Chemistry in Berland CodeForces - 846E

    题目 题意: 有n种化学物质,第i种物质现有bi千克,需要ai千克.有n-1种,编号为2-n的转换方式,每种都为(x,k),第i行是编号为i+1的转换方式,编号为i的转换方式(xi,ki)表示ki千克 ...

  7. Codeforces Round #Pi (Div. 2) E. President and Roads tarjan+最短路

    E. President and RoadsTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/567 ...

  8. 【CodeForces 567E】President and Roads(最短路)

    Description Berland has n cities, the capital is located in city s, and the historic home town of th ...

  9. codeforces 228E The Road to Berland is Paved With Good Intentions(2-SAT)

    Berland has n cities, some of them are connected by bidirectional roads. For each road we know wheth ...

随机推荐

  1. 信息论相关概念:熵 交叉熵 KL散度 JS散度

    目录 机器学习基础--信息论相关概念总结以及理解 1. 信息量(熵) 2. KL散度 3. 交叉熵 4. JS散度 机器学习基础--信息论相关概念总结以及理解 摘要: 熵(entropy).KL 散度 ...

  2. python 基础之简单购物车小程序实现

    购物车 all_list = [ ('mac',9000), ('kindle',900), ('tesla',800), ('python',105), ('bile',2000), ] savin ...

  3. JS闭包(2)

    利用闭包的特点,我们可以在封装自己的模块的时候只向外暴露我们模块中的数据,而不让其修改. 1.第一中封装的方式,新建一个myModule.js文件,这个模块的作用是对外部提供明天和后天的天气. 在my ...

  4. 吴裕雄--天生自然python数据清洗与数据可视化:MYSQL、MongoDB数据库连接与查询、爬取天猫连衣裙数据保存到MongoDB

    本博文使用的数据库是MySQL和MongoDB数据库.安装MySQL可以参照我的这篇博文:https://www.cnblogs.com/tszr/p/12112777.html 其中操作Mysql使 ...

  5. [蓝桥杯2015初赛]生命之树(树状dp)

    在X森林里,上帝创建了生命之树.他给每棵树的每个节点(叶子也称为一个节点)上,都标了一个整数,代表这个点的和谐值.上帝要在这棵树内选出一个非空节点集S,使得对于S中的任意两个点a,b,都存在一个点列 ...

  6. Duilib 修改程序exe、在任务栏以及任务管理器上的图标

    参考:https://blog.csdn.net/Rongbo_J/article/details/47379997       https://www.cnblogs.com/happinessda ...

  7. scala的trait执行报错: 错误: 找不到或无法加载主类 cn.itcast.scala.`trait`

    scala的trait执行报错: 错误: 找不到或无法加载主类 cn.itcast.scala.`trait`.Children 原因:包名写成了trait,与trait关键字重名了: package ...

  8. Manthan, Codefest 19 (open for everyone, rated, Div. 1 + Div. 2)D(树状数组)

    //树状数组中数组的特性,有更巧妙的方法.//我们知道在树状数组中,对于数组tree[i],它所维护的区间为[i−lowbit(i)+1,i]//所以对于tree[2^i],它所维护的区间就为[1,2 ...

  9. MySQL : INSERT INTO SELECT

    INSERT INTO wx_announcement_push ( title, content, STATUS, del_flag, user_login_name ) SELECT '大家好', ...

  10. EcShop二次开发学习方法

    EcShop二次开发学习方法 (2012-03-08 11:10:08) 转载▼ 标签: 京东 公用函数库 二次开发 sql语言 数据库设计 杂谈 分类: ecshop 近年来,随着互联网的发展,电子 ...