HDU-2955 Robberies 01背包 + 概率

来源：互联网发布：软件正版化实施方案编辑：程序博客网时间：2024/06/01 10:51

题目链接

刚开始以为概率就2位小数乘100来做WA

看了讨论区恍然大悟。

用成功逃走的概率当做价值！银行的总钱数当做背包容量！

#include <stdio.h>#include <string.h>#include <iostream>#include<functional>#include <queue>#include <string>#include <map>#include <algorithm>using namespace std;const int maxn = 106;const int inf = 1<<30;typedef __int64 LL;int n,V;float P,dp[maxn*maxn],p[maxn];int m[maxn];void GetDp(){memset( dp,0,sizeof(dp) );dp[0] = 1;for( int i = 0; i < n; i ++ ){for( int j = V; j - m[i] >= 0; j -- ){dp[j] = max( dp[j],dp[j-m[i]]*p[i] );}}}int main(){#ifndef ONLINE_JUDGE  freopen("data.txt","r",stdin);  #endif  int cas;scanf("%d",&cas);while( cas -- ){scanf("%f%d",&P,&n);P = 1 - P;V = 0;for( int i = 0; i < n; i ++ ){scanf("%d%f",&m[i],&p[i]);p[i] = 1-p[i];V += m[i];}GetDp();int flag = 0;for( int i = V; i >= 0; i -- ){if( dp[i] >= P ){flag = i;break;}}printf("%d\n",flag);}return 0;}

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