#include <stdio.h>
int factorial(int n) {
int i,result;
result=1;
for(i=n;i>1;i--){
result *= i;
}
return result;
}
int comb(int m,int k){
int x;
x=factorial(m)/(factorial(k)*factorial(m-k));
return x;
}
int main(void) {
int m,k;
printf("%d個の中から%d個を取り出す組み合わせは%d通りです。",m
,k
,comb
(m
,k
)); return 0;
}
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