ZOJ 3956 Course Selection System （dp 01背包）

思路

代码

#include <bits/stdc++.h>

#define mem(a,b) memset(a,b,sizeof(a))
#define rep(i,a,b) for(int i=a;i<b;i++)
const int INF=0x3f3f3f3f;
const int maxn=1e3+50;
const int mod=9901;
#define pii pair<int,int>
typedef long long ll;
typedef unsigned int ui;
using namespace std;

int w[maxn],c[maxn];
int dp[50050];
int main()
{
#ifndef ONLINE_JUDGE
//freopen("in.txt","r",stdin);
//freopen("out.txt","w",stdout);
#endif
int T,n; scanf("%d",&T);
while(T--){
scanf("%d",&n);
rep(i,0,n) scanf("%d %d",&w[i],&c[i]);
mem(dp,0);
rep(i,0,n)
for(int j=50000;j>=c[i];j--){
dp[j]=max(dp[j],dp[j-c[i]]+w[i]);
}
ll ans=0;
rep(i,0,50001){
ll totH=dp[i];
ans=max(ans,totH*totH-totH*i-(ll)i*i);
}
printf("%lld\n",ans);
}
return 0;
}