#include <iostream> /* including standard library */
 
    while ( condition == true ) {
    do something until condition untrue
    }

#include <iostream> /* including standard library */
 
using namespace std;
int main(void) {
    int i=0;
 
    while (i <= 99) {
        cout << i << endl;
        i++;
    }
    return 0;
}

  //output://
  
  0
  1
  2
  3
  4
  5
  6
  7
  ...
  up to 99