noip2006T1 能量项链

时间:2025-04-23 09:35:19

最近一直在做noip的题,由于太水一直没有写题解,可是这道题,这道题。啊啊啊啊……

明明水的要命,调了一节课啊!!我干脆不要搞OI了啊!

特别逗比的错误啊!!!!

代码:

#include <cstdio>
#include <cstring>
#include <iostream>
#include <cstdlib>
#include <algorithm>
#define N 251
using namespace std; int n;
int a[N][N];
int val[N]; int main()
{
scanf("%d", &n);
memset(a, , sizeof(a));
for (int i = ; i <= n; ++i)
{
int x; scanf("%d", &x);
val[i] = val[i+n] = x;
} for (int j = ; j < n; ++j)
for (int i = ; i <= *n, i+j <= *n; ++i) // i 一定要到 2*n !!!!!
for (int k = i; k < i+j; ++k)
a[i][i+j] = max(a[i][i+j], a[i][k] + a[k+][i+j] + val[i]*val[k+]*val[i+j+]);
int ans = ;
for (int i = ; i <= n; ++i)
ans = max(ans, a[i][i+n-]);
printf("%d\n", ans);
return ;
}