包AC，我老师教的，错了找我老师

#include<bits/stdc++.h>
#define ll long long
using namespace std;
ll f[25][25][25],vis[25][25][25];
ll w(ll a,ll b,ll c){
	if(a<=0||b<=0||c<=0)return 1;
	if(a>20||c>20||b>20)return w(20,20,20);;
	if(vis[a][b][c]!=0)return f[a][b][c];
	vis[a][b][c]=1;
	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(){
	ll a,b,c;
	while(true){
		cin>>a>>b>>c;
		if(a==-1&&b==-1&&c==-1){
			break;
		}
		cout<<"w("<<a<<", "<<b<<", "<<c<<") = "<<w(a,b,c)<<endl;
	}
	return 0;
}

#include <bits/stdc++.h>
using namespace std;
long long f[30][30][30];
long long w(long long a,long long b,long long 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]!=0) return f[a][b][c];
	
	if(a<b && b<c) f[a][b][c] = w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c);
	
	else 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);
	
	return f[a][b][c];
}
int main(){
	long long a,b,c;
	while(cin >> a >> b >>c){
		if (a==-1&&b==-1&&c==-1)return 0;
		cout<<"w("<<a<<", "<<b<<", "<<c<<") = "<< w(a,b,c)<<endl;
	
		
	}
	return 0;
}

#include <bits/stdc++.h>
using namespace std;
long long f[30][30][30];
long long w(long long a,long long b,long long 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]!=0) return f[a][b][c];
	
	if(a<b && b<c) f[a][b][c] = w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c);
	
	else 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);
	
	return f[a][b][c];
}
int main(){
	long long a,b,c;
	while(cin >> a >> b >>c){
		if (a==-1&&b==-1&&c==-1)return 0;
		cout<<"w("<<a<<", "<<b<<", "<<c<<") = "<< w(a,b,c)<<endl;
	
		
	}
	return 0;
}

#include <stdio.h>
#include <string.h>
#include <queue>
#include <math.h>
#include <vector>
#include <algorithm>
#include <iomanip>
#include <stack>
using namespace std;
long long num[30][30][30];
long long w(int a,int b,int c){
	long long ans =0;
	if(a<=0 || b<=0 || c<=0)return 1;
	if(a>20 || b>20 || c>20)return w(20,20,20);
	if(num[a][b][c]) return num[a][b][c];
	if(a<b && b<c) ans = w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c);
	else ans=w(a-1,b,c)+w(a-1,b-1,c)+w(a-1,b,c-1)-w(a-1,b-1,c-1);
	num[a][b][c]=ans;
	return ans;
}
int main(){
	long long a,b,c;
	while(cin >> a >> b >>c){
		if (a==-1&&b==-1&&c==-1)return 0;
		printf("w(%lld, %lld, %lld) = %lld\n",a,b,c,w(a,b,c)); 
	
		
	}
	return 0;
}//更简单

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <queue>
#include <math.h>
#include <vector>
#include <algorithm>
#include <iomanip>
#include <stack>

using namespace std;

#define LL long long
const int N =1e5+10;
const int INF =0x3f3f3f3f;
LL num [30][30][30];
LL 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(num [a][b][c])
		return num [a][b][c];
	LL ans=0;
	if(a<b&&b<c)
		ans= w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c);
	else
		ans= w(a-1,b,c)+w(a-1,b-1,c)+w(a-1,b,c-1)-w(a-1,b-1,c-1);
	num [a][b][c]=ans;
	return ans;
}
int main(){
	LL a,b,c;
	while(cin>>a>>b>>c){
	if(a==-1&&b==-1&&c==-1)
		return 0;
	printf("w(%lld, %lld, %lld) = %lld\n",a,b,c,w(a,b,c));
	}
return 0;
}

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <queue>
#include <math.h>
#include <vector>
#include <algorithm>
#include <iomanip>
#include <stack>

using namespace std;

#define LL long long
const int N =1e5+10;
const int INF =0x3f3f3f3f;
LL num [30][30][30];
LL 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(num [a][b][c])
		return num [a][b][c];
	LL ans=0;
	if(a<b&&b<c)
		ans= w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c);
	else
		ans= w(a-1,b,c)+w(a-1,b-1,c)+w(a-1,b,c-1)-w(a-1,b-1,c-1);
	num [a][b][c]=ans;
	return ans;
}
int main(){
	LL a,b,c;
	while(cin>>a>>b>>c){
	if(a==-1&&b==-1&&c==-1)
		return 0;
	printf("w(%lld, %lld, %lld) = %lld\n",a,b,c,w(a,b,c));
	}
return 0;
}

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <queue>
#include <math.h>
#include <vector>
#include <algorithm>
#include <iomanip>
#include <stack>

using namespace std;

#define LL long long
const int N =1e5+10;
const int INF =0x3f3f3f3f;
LL num [30][30][30];
LL 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(num [a][b][c])
		return num [a][b][c];
	LL ans=0;
	if(a<b&&b<c)
		ans= w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c);
	else
		ans= w(a-1,b,c)+w(a-1,b-1,c)+w(a-1,b,c-1)-w(a-1,b-1,c-1);
	num [a][b][c]=ans;
	return ans;
}
int main(){
	LL a,b,c;
	while(cin>>a>>b>>c){
	if(a==-1&&b==-1&&c==-1)
		return 0;
	printf("w(%lld, %lld, %lld) = %lld\n",a,b,c,w(a,b,c));
	}
return 0;
}