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while cycle (Example 1)

While cycle, if instruction, module operator (%)

Implement a C program that:

  • acquires 5 number from the keybord
  • computes how many even and odd numbers are inserted
  • prints the results of this computation


/* Insert 5 numbers using the keyboard and count how many even and odd numbers have been inserted */
#include <stdio.h>
#define NUMBERS 5
int main(){
  int n;
  int x;
  int n_even, n_odd;
    printf("Insert number %d: ", n);
    scanf("%d", &x);
    if (x%2 == 0) {
      n_even = n_even+1;
      n_odd = n_odd+1;
     n = n+1;
  printf("EVEN: %d - ODD: %d\n", n_even, n_odd);
  return 0;

The program executes 5 times the block of code inside the while cycle that:

  • asks the user to insert a number
  scanf("%d", &x);
  • checks if the number is even if (x%2 == 0) or odd (branch else of the if instruction)
  if (x%2 == 0) {
      /* Code executed if x is even */
      /* Code executed if x is odd */
  • in the case of an even, it increments the variable n_even, otherwise, in the case of an odd number, it increments the variable n_odd
  • at the ends of the while cycle the program prints the results
  printf("EVEN: %d - ODD: %d\n", n_even, n_odd);

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/membri/wiki/data/pages/cs/c_language/while_cycle_1.txt · Last modified: 2015/10/28 15:22 (external edit)

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