#include <stdio.h>
 
// 階乗を求める関数
int kaijo(int n) {
    int i, result = 1;
    for(i = 1; i <= n; i++) {
        result *= i;
    }
    return result;
}
 
// 組合せを求める関数
int comb(int m, int k) {
    return kaijo(m) / (kaijo(k) * kaijo(m - k));
}
 
int main() {
    int m, k;
    printf("mを入力してください：");
    scanf("%d", &m);
 
    printf("kを入力してください：");
    scanf("%d", &k);
 
    printf("%d個の中から%d個を取り出す組合せ数は、%d通りです。\n", m, k, comb(m, k));
 
    return 0;
}
 

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