从高位一位一位判定就行了呗
by __Aaaaaaaa @ 2024-04-10 19:55:22
@[__Aaaaaaaa](/user/338880)
所以具体咋实现
~~话说您是不是过于轻描淡写了（bushi~~
by a_little_carrot @ 2024-04-10 20:00:23
```
#include <iostream>
#include <cstdio>
using namespace std;
typedef long long ll;
const int N=110;
int n,m,a[N];
ll k,C[N][N];
int main(){
for(int i=0;i<=60;++i){
for(int j=0;j<=i;++j){
C[i][j]=j==0?1:C[i-1][j-1]+C[i-1][j];
}
}
cin>>n>>m>>k;
int s=n+m;
for(int i=1;i<=s;++i){
int c=C[n+m-1][n];
if(k>c){
k-=c;
--n;
putchar('b');
}
else{
putchar('a');
--m;
}
}
return 0;
}
```
by __Aaaaaaaa @ 2024-04-10 20:03:39
@[a_little_carrot](/user/1042960)
by __Aaaaaaaa @ 2024-04-10 20:03:55
@[__Aaaaaaaa](/user/338880) 感谢 已关
by a_little_carrot @ 2024-04-10 20:04:27
emm似乎要高精度
by __Aaaaaaaa @ 2024-04-10 20:04:49
@[__Aaaaaaaa](/user/338880) 然后似乎14pts
by a_little_carrot @ 2024-04-10 20:05:54
```
#include <iostream>
#include <cstdio>
using namespace std;
typedef long long ll;
const int N=110;
int n,m,a[N];
ll k,C[N][N];
int main(){
for(int i=0;i<=60;++i){
for(int j=0;j<=i;++j){
C[i][j]=j==0?1:C[i-1][j-1]+C[i-1][j];
}
}
cin>>n>>m>>k;
int s=n+m;
for(int i=1;i<=s;++i){
ll c=C[n+m-1][n];
if(k>c){
k-=c;
--n;
putchar('b');
}
else{
putchar('a');
--m;
}
}
return 0;
}
```
by __Aaaaaaaa @ 2024-04-10 20:06:08
因为我没开LL
by __Aaaaaaaa @ 2024-04-10 20:06:28
@[__Aaaaaaaa](/user/338880) 29了（
我还是试试加点火车头叭
by a_little_carrot @ 2024-04-10 20:09:57