13 lines
273 B
C++
13 lines
273 B
C++
#include<iostream>
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using namespace std;
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int main(){
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int n,k,f[21][21]={1};
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cin>>n>>k;
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for(int i=1;i<=n;i++){
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for(int j=1;j<=i;j++){
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f[i][j]=f[i-1][j]+f[i-1][j-1]*j;
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if(j==k) break;
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}
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}
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cout<<f[n][k];
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} |