RID: [146495061](https://www.luogu.com.cn/record/146495061)
by xk2013 @ 2024-02-07 21:33:41
本贴不玄关，但玄……玄[「YCOI」出题组](https://www.luogu.com.cn/team/60565)名额！
by xk2013 @ 2024-02-07 21:34:58
@[xk2013](/user/998662)
你最好不用三维数组，#1的a就是>200000
by sybnb @ 2024-02-08 22:04:46
只对于你的代码
by sybnb @ 2024-02-08 22:07:36
@[xk2013](/user/998662) 这是我的代码
```cpp
#include<iostream>
#include<cstdio>
using namespace std;
long long ans[35][35][35];
long long a, b, c;
long long f(long long a, long long b, long long c){
if(a <= 0||b <= 0||c <= 0)
{
return 1;
}
else if(a > 20||b > 20||c > 20)
{
return ans[20][20][20] ? ans[20][20][20] : ans[20][20][20] = f(20,20,20);
}
else if(a < b&b < c)
{
return ans[a][b][c] ? ans[a][b][c] : ans[a][b][c] = f(a,b,c-1) + f(a,b-1,c-1) - f(a,b-1,c);
}
else
{
return ans[a][b][c] ? ans[a][b][c] : ans[a][b][c] = f(a-1,b,c) + f(a-1,b-1,c) + f(a-1,b,c-1) - f(a-1,b-1,c-1);
}
}
int main(){
scanf("%lld%lld%lld", &a, &b, &c);
while(a != -1||b != -1||c != -1)
{
printf("w(%lld, %lld, %lld) = %lld\n", a, b, c, f(a,b,c));
scanf("%lld%lld%lld", &a, &b, &c);
}
return 0;
}
```
by sybnb @ 2024-02-08 22:20:55
@[xk2013](/user/998662) 记忆化搜索是先处理边界，在判断有没有算过，不是先判断，在处理边界。
by Abelxxyy @ 2024-02-25 09:24:26