#include <stdio.h>
 
int prime(int n);
 
void func(int n){
    static int count = 0;
    count ++;
 
    printf("%dは%d番目の素数\n", n, count);
}
int prime(int n){
    int i;
    int sosuu = 1;
    for(i = 2; i < n; i++){
        if(n % i == 0){
            sosuu = 0;
            break;
        }
    }
    return sosuu;
}
 
int main(void){
    int x;
    for(int i = 2; i < 20; i++){
        x = prime(i);
        if(x == 1){
            func(i);
        }
    }
    return 0;
}

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