#include <stdio.h>
void souda(int a){
static int c;
c++;
}
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 i,a;
for(i=2;i<20;i++){
a=prime(i);
if(a==1){
souda(i);
}
}
return 0;
}
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