完全揹包,升級所需n經驗,每個怪對應a經驗,b耐久,dp出最大耐久可以打到的最多經驗,同時注意最多隻能打s個怪:
#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
using namespace std;
const int N = 200;
int dp[N], w[N], p[N], Hash[N];
int main()
{
int n, m, k, s;
while(~scanf("%d%d%d%d", &n, &m, &k, &s))
{
memset(Hash, 0, sizeof(Hash));
memset(dp, 0, sizeof(dp));
memset(w, 0, sizeof(w));
memset(p, 0, sizeof(p));
for(int i=0; i<k; ++i)
scanf("%d%d", &w[i], &p[i]);
for(int i=0; i<k; ++i)//完全揹包
{
for(int j=p[i]; j<=m; ++j)
{
if(dp[j] < dp[j-p[i]]+w[i])
{
dp[j] = dp[j-p[i]] + w[i];
Hash[j] = Hash[j-p[i]] + 1;//對應j耐久打到的最大經驗所殺的怪的數量
}
}
}
int i, ok = 0;
for(i=0; i<=m; ++i)
{
if(dp[i]>=n && Hash[i]<=s)//判斷是否滿足題意
{
ok = 1;
break;
}
}
printf(ok==1? "%d\n" : "-1\n", m-i);
}
return 0;
}