0分，求助！！！（>.<）

#include<iostream>
using namespace std;
int l[22][22][22]={0};//记忆化，将中间过程记忆化，可节省多余计算
int w(int a, int b, int c) {
    if (a <= 0 || b <= 0 || c <= 0)return 1;
    if (a > 20 || b > 20 || c > 20)return w(20, 20, 20);
    if(l[a][b][c]!=0)return l[a][b][c];//先判断>20，后判断是否记忆化
    if (a < b && b < c) l[a][b][c]= w(a, b, c - 1) + w(a, b - 1, c - 1) - w(a, b - 1, c);
    else l[a][b][c]=w(a - 1, b, c) + w(a - 1, b - 1, c) + w(a - 1, b, c - 1) - w(a - 1, b - 1, c - 1);
    return l[a][b][c];
}
int main() {
    int a, b, c;
    while (true) {
        cin >> a >> b >> c;
        if (a == -1 && b == -1 && c == -1)break;
        printf("w(%d,%d,%d)=%d\n", a, b, c, w(a, b, c));
    }
    return 0;
}