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Count even and odd until -1

Short answer

Read numbers until -1; for each non-negative entry, increment even counter if n%2==0 else odd counter. -1 stops and is not counted. Print totals.

Write a program to read the number until -1 is encountered. Also count the number of even number and odd numbers entered by the user.

Numbers are read until -1 is entered (the -1 is not counted). A number is even if n % 2 == 0, otherwise it is odd.

#include <stdio.h>
int main(void)
{
    int n, even = 0, odd = 0;
    printf("Enter numbers (-1 to stop):\n");
    scanf("%d", &n);
    while (n != -1)
    {
        if (n % 2 == 0)
            even++;
        else
            odd++;
        scanf("%d", &n);
    }
    printf("Even numbers = %d\nOdd numbers = %d\n", even, odd);
    return 0;
}

Output for the input 4, 7, 10, 3, 8, 9, -1:

Enter numbers (-1 to stop):
Even numbers = 3
Odd numbers = 3

Even numbers are 4, 10, 8 (3 of them); odd numbers are 7, 3, 9 (3 of them).

✓ Answer checked by Claude Opus 5.5 (high effort)

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