C++ while loop

From all looping structures in C++ while is the simplest loop. It is called an entry-controlled loop because the conditions are tested before the start of the loop execution. The format of a while loop is given below:

while (test_condition) {
   body of the loop
}

If the test_condition is true then the body of the loop will be executed. After execution the test_condition is again evaluated and if it is true the body will be executed once. As long as the condition is true the process continues. When the test_condition finally becomes false the control will be transferred out of the loop and continues with the statement immediately after the body of the loop.

Flowchart of while loop:

Example of a while loop:

#include <iostream>
using namespace std;
int main() {
  int i = 1;
  while(i <= 10) {
    cout << i;
    i++;
  }
  return 0;
}

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