Greedy Algorithms PSET1. I wrote this code but at some cases it fails to give the correct output. Can someone please help me.?

Question

#include <stdio.h>
#include <math.h>

int main(void)
{
    float dollar;

    do                                      //Loop to prompt user to type positive value
    {
        printf("Value of change owned:");
        scanf("%f", &dollar);
    }
    while (dollar < 0);

    int cents = round(dollar * 100);       //To convert dollar to cents

    printf("Cents owned:%i\n",cents);

    int coin= 0;

    for (int i = 0; cents >= 25; i++)      //Loop to count number of coins needed
    {
        coin = 0 + 1;
        cents = cents - 25;
    }

    for (int j = 0; cents >= 10; j++)
    {
        coin = coin + 1;
        cents = cents - 10;
    }

    for (int k = 0; cents >= 5; k++)
    {
        coin = coin + 1;
        cents = cents - 5;
    }
    for (int l = 0; cents >= 1; l++)
    {
        coin = coin + 1;
        cents = cents - 1;
    }

    printf("Coins needed: %i\n",coin);
    return 0;
}

Answer 1

A simple oversight error. Look at this code:

for (int i = 0; cents >= 25; i++)      //Loop to count number of coins needed
{
    coin = 0 + 1;
    cents = cents - 25;
}

On each pass through the code, coin is set to 1. This means that any value over 49 cents will be wrong. It's not incremented because of the 0. I believe that you wanted to write coin = coin + 1;

Programming note: The usual way to increment a variable would be like this:

coin++;

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