10 10 1 10 1 1 10 10 1 9 1 1 9 10 2 10 1 1 2 2
0 -1 1
#include <stdio.h>
#include <string.h>
#define maxn 102
int dp[maxn][maxn];
int max(int a, int b) { return a > b ? a : b; }
int main() {
freopen("stdin.txt", "r", stdin);
int N, M, K, S;
int a, b, i, j, k;
while (~scanf("%d%d%d%d", &N, &M, &K, &S)) {
memset(dp, 0, sizeof(dp));
while (K--) {
scanf("%d%d", &a, &b);
for (i = 1; i <= S; ++i)
for (j = b; j <= M; ++j)
dp[i][j] = max(dp[i][j], dp[i-1][j-b] + a);
}
if (dp[S][M] < N) {
printf("-1\n");
} else {
for (i = 1; i <= M; ++i) {
if (dp[S][i] >= N) {
printf("%d\n", M - i);
break;
}
}
}
}
return 0;
}原文:http://blog.csdn.net/chang_mu/article/details/41556767