POJ 1579 Function Run Fun(记忆化搜索)

题目链接：点击打开链接

题意很简单，记忆化搜索的水题......

// POJ 1579 Function Run Fun.cpp
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <iostream>
using namespace std;
int dp[25][25][25];
int dfs(int a, int b, int c) {
if (a <= 0 || b <= 0 || c <= 0) {
return 1;
}
if (a > 20 || b > 20 || c > 20) {
return dfs(20, 20, 20);
}
if (dp[a][b][c] != -1) {
return dp[a][b][c];
}
else if (a < b && b < c) {
dp[a][b][c] = dfs(a, b, c - 1) + dfs(a, b - 1, c - 1) - dfs(a, b - 1, c);
return dp[a][b][c];
}
else {
dp[a][b][c] = dfs(a - 1, b, c) + dfs(a - 1, b - 1, c) + dfs(a - 1, b, c - 1) - dfs(a - 1, b - 1, c - 1);
return dp[a][b][c];
}
}
int main(){
int a, b, c;
memset(dp, -1, sizeof(dp));
while (scanf("%d%d%d", &a, &b, &c) != EOF) {
if (a == -1 && b == -1 && c == -1) {
break;
}
printf("w(%d, %d, %d) = %d\n", a, b, c, dfs(a, b, c));
}
return 0;
}