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when i check50 my code I get this message :

:( print_winner identifies Bob as winner of election
    print_winner function did not print winner of election
:( print_winner identifies Charlie as winner of election
    print_winner function did not print winner of election

i tried the test 3 candidates a,b,c 4 voters who vote: a,b,b,c. The result i got is a c so there is something wrong but I can't see where.

I don't understand why it is not properly sorted in this case while in many other case my bubble sort is working.

Could you please explain or give a hint ? Many thanks

Here is my code

#include <stdio.h>
#include <string.h>

// Max number of candidates
#define MAX 9

// Candidates have name and vote count
typedef struct
{
    string name;
    int votes;
}
candidate;

// Array of candidates
candidate candidates[MAX];

// Number of candidates
int candidate_count;

// Function prototypes
bool vote(string name);
void print_winner(void);

int main(int argc, string argv[])
{
    // Check for invalid usage
    if (argc < 2)
    {
        printf("Usage: plurality [candidate ...]\n");
        return 1;
    }

    // Populate array of candidates
    candidate_count = argc - 1;
    if (candidate_count > MAX)
    {
        printf("Maximum number of candidates is %i\n", MAX);
        return 2;
    }
    for (int i = 0; i < candidate_count; i++)
    {
        candidates[i].name = argv[i + 1];
        candidates[i].votes = 0;
    }

    int voter_count = get_int("Number of voters: ");

    // Loop over all voters
    for (int i = 0; i < voter_count; i++)
    {
        string name = get_string("Vote: ");

        // Check for invalid vote

        if (!vote(name))
        {
            printf("Invalid vote.\n");
        }
    }

    // Display winner of election
    print_winner();
}

// Update vote totals given a new vote
bool vote(string name)
{
    for (int i = 0 ; i < candidate_count ; i++)

        if (strcmp(name, candidates[i].name) == 0)
        {
            candidates[i].votes++;
            return true;
        }
    return false;

}

// Print the winner (or winners) of the election
void print_winner(void)
{
    for (int i = 0 ; i < candidate_count - 1 ; i++)
    {
        for (int c = 0 ; c < i - candidate_count - 1 ; c++)
        {
            if (candidates[c].votes < candidates[c + 1].votes)
            {
                int swap = candidates[c].votes;
                candidates[c].votes = candidates[c + 1].votes;
                candidates[c + 1].votes = swap;
            }

        }
    }
    printf("%s\n", candidates[0].name);

    for (int i = 0 ; i < candidate_count - 1 ; i++)
    {
        if ((candidates[i + 1].votes) == (candidates[0].votes))
        {
            printf("%s\n", candidates[i + 1].name);
        }
    }
}
1

The problem is in this condition in your second 'for' loop: for (int c = 0 ; c < i - candidate_count - 1 ; c++). Let's see: Before execute the second loop i = 0 and c = 0. To run the code 'c < i - candidate_count -1' has to be true. if i = 0, and you substrate candidate_count and 1, the result is always going to be negative so the code in the second loop will never execute.

| improve this answer | |
  • Hi, thanks for your answer. I changed my second loop to : for (int c = 0 ; c <= candidate_count - i - 1 ; c++) but it still doesn't work even though the condition is true this time. I still go the same results – Martinf Apr 20 at 13:03
  • In the Code inside your 'for' loops you change the number of votes linked to each candidate. Are you sure you want to do that? – Tritum Apr 20 at 13:33
  • No ! thanks for the hint, I changed it to the names in my array but it doesn't seems right to me ```` for (int c = 0 ; c < candidate_count - i - 1 ; c++) { if (candidates[c].votes < candidates[c + 1].votes) { string swap = candidates[c].name; candidates[c].name = candidates[c + 1].name; candidates[c + 1].name = swap; ```` When i do this it only swap the name ? So my vote values attached to each name will change for the next loop no ? – Martinf Apr 20 at 14:12
  • What I meant is that candidates[x].name and candidate[x].votes are linked together and if you change one of them you won't be able to determine how many votes got candidate[x] when you have to print them. You could take a step back and think: what's the purpose of this part of the code? is there a way that you can keep track of the votes and determine which is the largest number of them without changing the array candidates? – Tritum Apr 20 at 14:37
  • Hey thanks for your help I finally managed to do it ! I just simply stored the max vote in an integer. – Martinf Apr 22 at 8:34

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