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View Code #include#include #include #include using namespace std;#define maxn 25int a, b, c;int f[maxn][maxn][maxn];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 (f[a][b][c] != -1) return f[a][b][c]; if (a < b && b < c) return f[a][b][c] = w(a, b, c - 1) + w(a, b - 1, c - 1)- w(a, b - 1, c); return f[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);}int main(){ memset(f, -1, sizeof(f)); //freopen("t.txt", "r", stdin); while (scanf("%d%d%d", &a, &b, &c), ~a | ~b | ~c) printf("w(%d, %d, %d) = %d\n", a, b, c, w(a, b, c)); return 0;}