[C] text file 정렬

input.txt

0, 5, 9, 7, 5, 3, 2, 4, 8, 6, 9, 10, 31, -1, 25, -5, -4, -9, 1, 2, 8, 6, 7, 4, 9, 1, 0, 20, 83, 

147, -3, -8, -6, 2, -8, 14, 8, 3, 4, 85, -7, 69, 14, 85, 75, 1000, 32, -50, -44, -9009, -48, 68, 52

#include <stdio.h>

void bubble(int arr[], int num);
void select(int arr[], int num);

void main(){
    int buf[100] = {0, };
    FILE *fp = fopen("input.txt", "r");
    int count = 0;
    int i = 0;
    while(!feof(fp)){
        fscanf(fp, "%d, ", &buf[count]);
        count++;
    }   
    fclose(fp);

//  bubble(buf, count);
    select(buf, count);
    FILE *fr = fopen("output.txt", "w");
    while(i < count){
        fprintf(fr, "%d, ", buf[i]);
        i++;
    }   
    fclose(fr);
    printf("\n");
}

// 버블 정렬
void bubble(int arr[], int num){
    int i, j;
    int temp = 0;
    for(i = 0; i < num; i++){
        for(j = 0; j < num - 1; j++){
            if(arr[j] > arr[j + 1]){
                temp = arr[j];
                arr[j] = arr[j + 1];
                arr[j + 1] = temp;
            }
        }
    }
}

// 선택 정렬
void select(int arr[], int num){
    int i, j;
    int min;
    int temp = 0;
    for(i = 0; i < num - 1; i++){
        min = i;
        for(j = i + 1; j < num ; j++){
            if(arr[j] < arr[min])
                min = j;
        }
        temp = arr[min];
        arr[min] = arr[i];
        arr[i] = temp;
    }
}

output.txt

-9009, -50, -48, -44, -9, -8, -8, -7, -6, -5, -4, -3, -1, 0, 0, 0, 1, 1, 2, 2, 2, 3, 3, 4, 4, 4, 5,
5, 6, 6, 7, 7, 8, 8, 8, 9, 9, 9, 10, 14, 14, 20, 25, 31, 32, 52, 68, 69, 75, 83, 85, 85, 147, 1000,