#include <stdio.h>
int comb(int n, int k){
int N=n,K=k;
if (k==n){
return 1;
}
else if(K==1){
return n;
}
else{
for(int i=1;i<k;i++){
N=N*(n-i);
K=K*(k-i);
}
return N/K;
}
}
int main(void) {
int n, k;
return 0;
}
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