#include <bits/stdc++.h>
using namespace std;
long long w_res[21][21][21], x, y, z, i, j, k;
#define w_res_init_num -9223372036854775808
long long w(long long a, long long b, long long c) {
	printf ("[wsDbg][Line5][clock%d] a=%lld,b=%lld,c=%lld,w_res[a][b][c]=%lld\n", clock(),a,b,c,w_res[a][b][c]);
	if (w_res[a][b][c] != w_res_init_num) return w_res[a][b][c];
	if (a < 0 || b < 0 || c < 0) return w (0, 0, 0); if (a > 20 || b > 20 || c > 20) return w (20, 20, 20);
	if (a < b && b < c) w_res[a][b][c] = w (a, b, c - 1) + w (a, b - 1, c - 1) - w (a, b - 1, c);
	else w_res[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 w_res[a][b][c];
}
int main() {
	for (i = 0; i < 21; i++) for (j = 0; j < 21; j++) for (k = 0; k < 21; k++) w_res[i][j][k] = w_res_init_num;
	// memset (w_res, -9223372036854775808, sizeof (w_res)); w_res[0][0][0] = 1;
	while (true) {
		scanf ("%lld%lld%lld", &x, &y, &z);
		if (x == -1 && y == -1 && z == -1) break;
		else printf ("w(%lld, %lld, %lld) = %lld\n", x, y, z, w (x, y, z));
	}
	return 0;
}

谢谢辣~！（请先看一看评论，或许我自己解决了呢？）

悬赏一个关注 ，然后在我弟弟面前装个B

验证码RETN祭