#include<iostream>
using namespace std;

int main() {

     int max = 100;
     int value;
     int keepreading;

     keepreading = 1;
     do {
         cout << "Enter a positive integer (<= " << max << ") : ";
         cin  >> value;

         if (cin.fail()) {   // check for failure
             cerr << "Invalid character.  Try Again." << endl;
             cin.clear();
             cin.ignore(2000, '\n');
         } else if (value <= 0 || value > max) {
             cerr << value << " is outside the range [1," <<
                  max << ']' << endl;
             cerr << "Invalid input.  Try Again." << endl;
             cin.ignore(2000, '\n');
         } else if (char(cin.get()) != '\n') {
             cerr << "Trailing characters.  Try Again." << endl; 
             cin.ignore(2000, '\n');
         } else
             keepreading = 0;
     } while(keepreading == 1);

     return value;
 }