Mode of an array in C

[willingj]

I am continuing work on a program for analysis of an entered array, I have got min,max,median and sorting the array working with some input parameters. I cannot seem to get the mode to work, i have attempted some code to do this. Your help would be greatly appriciated, i am eager to learn how to accomplish these things.
Code:

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

#define N 100
#define MINVAL 0 /* the lowest allowable data value */ 
#define MAXVAL 100 /* the highest allowable data value */ 

int main()
{
    int a[N] = {0};
    int i, j, value, n;

    int freq[MAXVAL + 1 - MINVAL] = { 0 }; /* clear the frequency counts to 0. */
    size_t k = 0; /* loop counter */ 
    int mode = 0; /* for recording the modal value */ 

    printf("Please enter array: To sort Array enter 0  \n");  

    // Upto 100 items can be created in a[i]   
    scanf("%d", &a[0]);        
    for(i = 1; i < N && a[i-1] < 100 && a[i-1] != 0; i++)          
    {   
        // Input of the numbers into array a[i]   
        scanf("%d", &a[i]);  
    }   
    n = i;    

    if(a[n-1] > 100) 
    {        
        printf("Number must be between 0 and 100");   
        exit(1);   
    }   

    if (a[n-1] == 0)  
    {           
        a[n-1] = 0;    
        n--;    
    }    


    for(k = 0; k < sizeof a / sizeof a[0]; k++) /* for each datum */ 
    {   
        ++freq[a[k]]; /* track the frequency */ 
        if(freq[a[k]] > mode) /* is this now the most common item? */ 
        {   
            mode = a[k]; /* yes, so log it */ 
        }   
    }   
    printf("The modal value is %d which occurs %d time%s\n", 
            mode, 
            freq[mode], 
            freq[mode] == 1 ? "" : "s"); /* 1 time, 2 time>>s<< */

    printf("Sorted List: ");    

    // Simple insertion sort    
    for(i = 1; i < n; i++) 
    {             
        value = a[i];            
        for (j = i - 1; j >= 0 && a[j] > value; j--)
            a[j + 1] = a[j];
        a[j + 1] = value;
    }

    //Prints the sorted array    
    for(i = 0; i < n; i++)
        printf("%d ", a[i]);
    printf("\n");
    printf("Min: %d\n", a[0]);
    printf("Max: %d\n", a[n-1]);
    printf("Median: %f\n", n % 2 ? a[n/2] : 0.5*(a[n/2] + a[n/2-1]));
}

[Luckychap]

What you want from us to do from this crapy code. No code tags, no comments.

Please put code tags and comments in your code.

[akulkarni]

use two fors for sort i=0 to n-1 j=i+1 to n