听取 WA 声一片（即答
by fengziyi @ 2023-02-23 19:15:56
你把输出格式读一遍就知道了
by C20220215 @ 2023-02-23 19:17:56
改了，20pts
```
#include<iostream>
using namespace std;
long long flag[50][50][50];
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){
if(flag[20][20][20] == -1){
flag[20][20][20] = w(20,20,20);
}
return flag[20][20][20];
}else if(a<b && b<c){
if(flag[a][b][c] == -1){
flag[a][b][c] = w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c);
}
}else{
if(flag[a][b][c] == -1){
flag[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 flag[a][b][c];
}
int main(){
long long a,b,c;
for(int i = 0;i<=20;i++){
for(int j = 0;j<=20;j++){
for(int k = 0;k<=20;k++){
flag[i][j][k] = -1;
}
}
}
scanf("%lld%lld%lld",&a,&b,&c);
printf("w(%lld, %lld, %lld) = %lld\n",a,b,c,w(a,b,c));
while(a!=-1&&b!=-1&&c!=-1){
scanf("%lld%lld%lld",&a,&b,&c);
if(a!=-1&&b!=-1&&c!=-1){
printf("w(%lld, %lld, %lld) = %lld\n",a,b,c,w(a,b,c));
}
}
return 0;
}
```
求dalao好人做到底
by _Coffice_ @ 2023-02-25 08:27:06
@[czw20110831](/user/868063)
感觉也不难这题，直接递推完事。 附上我的AC代码，你参考下。
```cpp
#include <bits/stdc++.h>
using namespace std;
#define f(i,a,b) for(int i=a;i<=b;i++)
#define g(i,a,b) for(int i=a;i>=b;i--)
long long w[21][21][21];
void init() {
f(i,0,20) {
f(j,0,20) {
f(k,0,20) {
if(i==0||j==0||k==0) w[i][j][k]=1;
else {
if(i<j&&j<k) w[i][j][k]=w[i][j][k-1]+w[i][j-1][k-1]-w[i][j-1][k];
else {
w[i][j][k]=w[i-1][k][j]+w[i-1][j-1][k]+w[i-1][j][k-1]-w[i-1][j-1][k-1];
}
}
}
}
}
}
int main(){
int a,b,c,i=0;
init();
while(~scanf("%d %d %d",&a,&b,&c)&&!(a==-1&&b==-1&&c==-1)) {
if(a<0||b<0||c<0) printf("w(%d, %d, %d) = %lld\n",a,b,c,1);
else {
if(a>20||b>20||c>20) printf("w(%d, %d, %d) = %lld\n",a,b,c,w[20][20][20]);
else {
printf("w(%d, %d, %d) = %lld\n",a,b,c,w[a][b][c]);
}
}
};
return 0;
}
```
by mooktian @ 2023-02-25 20:12:02
Thanks♪(･ω･)ﾉ
by _Coffice_ @ 2023-02-26 08:47:38