Keeping count of times user inputs a number in C

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My problem in this program is that when I run the program, I am somehow getting a much larger than expected number for my count variable. Example: in do-while, I may enter 25, and 50 again and get a sum of 75, but a count in the thirty-thousands. Any direction here?

#include <stdio.h>
#include <stdlib.h>

int main()
{
    // 1) Read number from user
    int userInput, doubleInput;
    printf("Please enter a number: ");
    scanf("%d", &userInput);

    // 2) Double the number & print it
    doubleInput = userInput * 2;
    printf("Value of user input multiplied by 2: %d\n", doubleInput);

    // 3) Using a loop, print the original userInput out 9 times
    for (int i = 1; i < 10; i++)
    {
        printf("Print Line %d of 9. User input: %d\n", i,  userInput);
    }

    // 4) Ask the user to enter numbers & keep reading until the sum > 50
    int sum, count, addToSum  = 0;
    do
    {
        printf("Keep entering numbers, program will stop when sum > 50: ");
        scanf("%d", &addToSum);
        count = count + 1;
        sum = sum + addToSum;
    } while (sum < 50);
    printf("The sum is %d and the number of values inputed is %d", sum, count);
}
c
1 Answers

You must initialize the variables count and sum before using their values to calculation. Otherwise, the initial values of them are indeterminate and using the values invokes undefined behavior.

Wrong line:

int sum, count, addToSum  = 0;

It should be:

int sum = 0, count = 0, addToSum  = 0;
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