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

void count_ints(const char* file_name) {
    FILE* file = fopen(file_name, "r");

    int arr[1000000];
    int n = sizeof(arr) / sizeof(arr[0]);
    int c = 0;

    while(!feof(file)) {
        fscanf(file, "%d", &arr[c]);
        c++;
    }
    // Hash table
    int hash[1000] = {0};
 
    int lv = 0, lvi = 0;

    for (int j=0; j<n; j++) {
        hash[arr[j]]++;
    }
 
    for (int i=0; i < 1000; i++) {
        if (lv <= hash[i]) {
            lv = hash[i];
            lvi = i;
        } 
    }

        printf("%d occurs %d times\n", lvi, lv);

    fclose(file);
}

int main() {

    count_ints("/home/russellb/Development/c_devel/play/fcountr/1M.txt");

    return 0;

Approach
1. Read the input file
2. Create hashtable
3. Find the maximum from the hash tableInitial approach was to use binary search. Later I learnt hash tables can be used for this problem and adopted it.

Result 142 occurs 1130 times

**Execution time**
real    0m00.11s
user    0m00.10s
sys 0m00.00s



Machine details:

CPU: Intel i5-3230M (4 cores)

OS: GNU/Linux

RAM: 8GM DDR3


}

Approach

1. Read in the file

2. Create hashmap of counts

3. Find the most occuringg value

CPU: i5-3235M

RAM: 8GB DDR3

OS: GNU/Linux

Execution times

\> time ./countr_ic

142 occurs 1130 times

real 0m00.10s

user 0m00.10s

sys 0m00.00s

Max finding is not optimized and working on it.