PreInPost.c

#include<stdio.h>

void PreInPost(int n){
    if(n==0)
     return;
    printf("Pre %d\n",n);
    PreInPost(n-1);
    printf("In %d\n",n);
    PreInPost(n-1);
    printf("Post%d\n",n);
    return;
}
int main(){
    int n;
    printf("Enter a number : ");
    scanf("%d",&n);
    PreInPost(n);
    return 0;
}