题意是:给定一组整数,通过移动使这个序列变为递增的,移动i元素的话费为i
例如 2 2 5 3 4通过移动5使得序列变为2 2 3 4 5故最小花费为5,如果移动3 4那么花费会为7
这道题可以通过求“最重上升子序列”来间接地得到结果,
dp[i]表示以weight[i]
为终点递增的最重的一系列书的重量之和。状态转移方程是
dp[i] = max(dp[i], dp[k] + weight[i]) (1 <= k <= i && weight[i] >= weight[k])
所以最后的答案是sum(weight[i])-max(dp[i])
代码如下:
#include<cstdio>
#include<cstring>
#include<cmath>
#include<cstdlib>
#include<iostream>
#include<algorithm>
#include<vector>
#include<map>
#include<queue>
#include<stack>
#include<string>
#include<map>
#include<set>
using namespace std;
#define LL long long
//const int maxn = ;
const int INF = 1000000000;
//freopen("input.txt", "r", stdin);
const int maxn = 100 + 5;
int dp[maxn], weight[maxn];
int sums, n;
int main() {
int test_case;
scanf("%d", &test_case);
while (test_case--) {
scanf("%d", &n);
sums = 0;
for (int i = 1; i <= n; i++) {
scanf("%d", &weight[i]);
sums += weight[i];
}
for (int i = 1; i <= n; i++) {
dp[i] = weight[i];
for (int j = i - 1; j >= 1; j--) {
if (weight[j] <= weight[i]) {
dp[i] = max(dp[i], dp[j] + weight[i]);
}
}
}
int ans = 0;
for (int i = 1; i <= n; i++) {
if (dp[i] > ans) {
ans = dp[i];
}
}
printf("%d\n", sums - ans);
}
return 0;
}
hust校赛c题 Move the Books(“最重上升子序列”)
原文:http://blog.csdn.net/u014664226/article/details/45920833