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#include<bits/stdc++.h>
using namespace std;
long long f[25][25][25];
long long w(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 w(20,20,20);
    else if(f[a][b][c]) return f[a][b][c];
    else 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)
            break;
        printf("w(%lld, %lld, %lld) = %lld",a,b,c,w(a,b,c));}
    return 0;
}

评测记录