大意: 给定序列, 每次操作可以任选一个数+1/-1, 求最少操作数使序列严格递增. 序列全-i后转化为求最少操作数使序列非降, 那么贪心可以知道最后$a_i$一定是修改为某一个$a_j$了, 暴力dp即可. #include <iostream> #include <cstdio> #define REP(i,a,n) for(int i=a;i<=n;++i) using namespace std; typedef long long ll; const int N =…

[题目链接] http://codeforces.com/problemset/problem/713/C [题目大意] 给出一个数列,请你经过调整使得其成为严格单调递增的数列,调整就是给某些位置加上或者减去某个数,调整的代价是加上或者减去的数的绝对值之和,请你输出最小代价. [题解] 先考虑这样一个问题,如果是非严格单调递增该如何做,我们会发现每次调整,都是调整某个数字为原先数列中存在的数字,最后才是最优的,所以,我们设DP[i][j]表示前i个数字,最后一个数为原先数列排序后第j大的数字的最…

C. Sonya and Problem Wihtout a Legend 题目连接: http://codeforces.com/contest/713/problem/C Description Sonya was unable to think of a story for this problem, so here comes the formal description. You are given the array containing n positive integers. A…

E. Sonya and Problem Wihtout a Legend time limit per test 5 seconds memory limit per test 256 megabytes input standard input output standard output Sonya was unable to think of a story for this problem, so here comes the formal description. You are g…

题目链接: C. Sonya and Problem Wihtout a Legend time limit per test 5 seconds memory limit per test 256 megabytes input standard input output standard output Sonya was unable to think of a story for this problem, so here comes the formal description. You…

[题目]C. Sonya and Problem Wihtout a Legend [题意]给定n个数字,每次操作可以对一个数字±1,求最少操作次数使数列递增.n<=10^5. [算法]动态规划+前缀和优化 [题解]★令b[i]=a[i]-i,则a[i]递增等价于b[i]不递减. 这样做之后,显然数字加减只能到b[i]中出现的数字,而不会出现其它数字. 令f[i][j]表示前i个数,第i个数字大小为c[j](第j大的数字)的最少操作次数. f[i][j]=abs(b[i]-c[j])+min{f…

C - Sonya and Problem Wihtout a Legend 思路:感觉没有做过这种套路题完全不会啊.. 把严格单调递增转换成非严格单调递增,所有可能出现的数字就变成了原数组出现过的数字. #include<bits/stdc++.h> #define LL long long #define fi first #define se second #define mk make_pair #define PII pair<int, int> #define PLI…

C. Sonya and Problem Wihtout a Legend time limit per test 5 seconds memory limit per test 256 megabytes input standard input output standard output Sonya was unable to think of a story for this problem, so here comes the formal description. You are g…

E. Sonya and Problem Wihtout a Legend time limit per test 5 seconds memory limit per test 256 megabytes input standard input output standard output Sonya was unable to think of a story for this problem, so here comes the formal description. You are g…

题目链接   Sonya and Problem Wihtout a Legend 题意  给定一个长度为n的序列,你可以对每个元素进行$+1$或$-1$的操作,每次操作代价为$1$. 求把原序列变成严格递增子序列的所需最小花费. 考虑$DP$. 首先比较常见的套路就是把每个$a[i]$减去$i$,然后把这个新的序列升序排序,记为$b[i]$. 这里有个结论:最后操作完成之后的每个数都是$b[i]$中的某个数. 然后就可以$DP$了,令$f[i][j]$为前$i$个数操作之后每个数都小于等于$b…