Sorting an array with Insertion Sort

Question

My task is to write a function naive_sort() that takes an array of random generated integers as a parameter and sorts them. I need to use Insertion Sort. I have come to a point where i have no idea how to fix the problem, when i run the program nothing happens. Console stays empty.I'm fairly new to C programming so don't be surprised if you find a stupid mistake somewhere. Any help would be greatly appreciated.

EDIT: It's outputting a list of numbers but they are not being sorted, output example:

558915997481717626
152655717476818999

This is my code(EDITED):

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

//Insertion Sort function to Sort Integer array list
int *naive_sort(int array[],int n)
{
    int j,temp,i;

    //Iterate start from second element
    for (i = 1; i < n; i++)
    {
        j = i;
        //Iterate and compare till it satisfies condition
        while ( j > 0 && array[j] < array[j-1])
        {
            //Swapping operation
            temp = array[j];
            array[j]   = array[j-1];
            array[j-1] = temp;
            j--;
        }
    }
    //return Sorted array
    return array;
}

int main()
{
    //declaring variables
    int array[10],i;
    int n = 10;

    srand (time(NULL)); //initialize random seed
    for (i=0; i<n; i++)
    {
            array[i] = rand() % 100;
            scanf("%d",&array[i]);
    }
    for(i=0; i<n; i++)
    {
        printf("%d", array[i]);
    }
    printf("\n");


    //calling naive_sort function defined above and getting
    //sorted array in sortArray variable
    naive_sort(array,n);

    //print sorted array
    for(i = 0; i<n; i++ )
    {
        printf("%d",array[i]);
    }
    printf("\n");
    return 0;
}

Is the `return 0;` in the middle of your main function intended? Seems to me like this program would never call naive_sort if you exit from the main function... But did you means that this program doesn't output anything at all? Not even the "arr[0]=X" part? — MartinVeronneau, Jan 27 '16 at 20:45
It wasn't intended, i forgot about it. I have fixed it now, the program is outputting something but numbers are not being sorted =/ — Lurem, Jan 28 '16 at 08:52

Rabbid76 · Accepted Answer · 2016-01-28T09:55:25.217

You didn' t initialze your local variable n, there is a return statment in the middle of your code, you access your array out of bounds in the first for loop (because of <=100). Adapt your code like this:

#include <stdio.h>      // printf, scanf
#include <stdlib.h>     // srand, rand
#include <time.h>       // time 

int main()
{
    int array[100], i;
    int n = 100; // init n

    srand (time(NULL)); // initialize random seed
    for( i=0; i<n; i++ )
    {
        array[i] = rand() % 100; // replace this by scanf to read values from input
        // scanf("%d",&array[i]); 
    }
    for( i=0; i<n; i++ )
    {
        printf("%4d",array[i]);
    }
    printf( "\n" );

    naive_sort(array,n); // sort array

    for( i=0; i<n; i++ )
    {
        printf("%4d", array[i]);
    }
    printf( "\n" );
    return 0;
}

Your function naive_sort works as expected.

Your code has helped make my program work Rabbid76, greatly appreciated. Unfortunately the numbers are not getting sorted. I have updated my first post with the output i am getting together with the latest code — Lurem, Jan 28 '16 at 08:50

Sorting an array with Insertion Sort

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