HDU_1171 Big Event in HDU(生成函数)

　　比1085多了一些变化，见代码。

My Code：

#include <iostream>
#include <cstring>
#include <cstdio>

using namespace std;

const int N = 250007;

struct node {
    int val;
    int num;
} a[55];

int c1[N], c2[N];


int main() {
    //freopen("data.in", "r", stdin);

    int n, i, j, sum, k;
    while(cin >> n) {
        if(n < 0)    break;
        memset(c1, 0, sizeof(c1));
        memset(c2, 0, sizeof(c2));

        for(i = 1; i <= n; ++i) {
            scanf("%d%d", &a[i].val, &a[i].num);
        }

        for(i = 0; i <= a[1].num * a[1].val; i += a[1].val) {
            c1[i] = 1; c2[i] = 0;
        }

        sum = a[1].num * a[1].val;   
        for(i = 2; i <= n; ++i) {
            for(j = 0; j <= sum; ++j) {
                for(k = 0; k <= a[i].num * a[i].val; k += a[i].val) {    //here
                    c2[k+j] += c1[j];
                }
            }
            for(j = 0; j <= sum + a[i].num * a[i].val; ++j) {
                c1[j] = c2[j]; c2[j] = 0;
            }
            sum += a[i].num * a[i].val;
        }
        for(i = sum/2; i >= 0; --i)
            if(c1[i] != 0)    break;

        printf("%d %d\n", sum - i, i);
    }
    return 0;
}