Sicily 1077 Cash Machine

多重揹包問題

#include <stdio.h>
#include <vector>
#include <memory.h>
using namespace std;
int dp[100010];
vector<int> items;
int get_max(int a, int b) {
    if (a>b)
        return a;
    else
        return b;
}
int main() {
    int total,n,nk,dk;
    int i,j;

    while (scanf("%d",&total)!=EOF) {
        scanf("%d",&n);
        items.clear();
        for (i=0;i<n;i++) {
            scanf("%d%d",&nk,&dk);
            for (j=1;j<=nk/2;j=j*2) {
                items.push_back(j*dk);
            } 
            items.push_back(dk*(nk-j+1));
        }
        memset(dp,0,sizeof(dp));
        for (i=0;i<items.size();i++) {
            for (j=total;j>=items[i];j--) 
                dp[j]=get_max(dp[j], dp[j-items[i]]+items[i]);
        }
        printf("%d\n", dp[total]);
    }
    return 0;
}