【HDOJ】1709 The Balance

母函数，指数可以为1也可以为-1，扩大指数加消减发现TLE，于是采用绝对值就过了。

#include <stdio.h>
#include <string.h>

#define MAXNUM 10001

int c1[MAXNUM], c2[MAXNUM];
int w[101];

int myabs(int x) {
    return x<0 ? -x:x;
}

int main() {
    int n, sum, tmp;
    int i, j, k;

    while (scanf("%d", &n) != EOF) {
        sum = 0;
        for (i=1; i<=n; ++i) {
            scanf("%d", &w[i]);
            sum += w[i];
        }
        memset(c1, 0, sizeof(c1));
        memset(c2, 0, sizeof(c2));
        c1[0] = 1;
        c1[w[1]] = 1;
        tmp = w[1];
        for (i=2; i<=n; ++i) {
            for (j=0; j<=tmp; ++j)
                for (k=0; k<=w[i]; k+=w[i]) {
                    c2[k+j] += c1[j];
                    c2[myabs(k-j)] += c1[j];
                }
            tmp += w[i];
            for (j=0; j<=tmp; ++j) {
                c1[j] = c2[j];
                c2[j] = 0;
            }
        }
        k = 0;
        for (i=1; i<=sum; ++i) {
            if (c1[i] == 0)
                c2[k++] = i;
        }
        printf("%d
", k);
        for (i=0; i<k; ++i)
            if (i)
                printf(" %d", c2[i]);
            else
                printf("%d", c2[i]);
        if (k)
            printf("
");
    }

    return 0;
}