merge sort

merge_sort.c

#include <stdio.h>

#define NUM_SCORE 15

void merge(int arr[], int start, int q, int end){
	int temp_arr[end-start+1];

	int i=start, j= q+1;

	for(int k=0; k<(end-start+1); k++){

		if( arr[i]>=arr[j]){
			temp_arr[k] = arr[i];
			i++;
			if( i>q ){
				for(int p=j; p<=end; p++){
					temp_arr[++k] = arr[p]; 
				} 

				break;
			}

		}else{
			temp_arr[k] = arr[j];
			j++;
			if( j>end ){
				for(int p=i; p<=q; p++){
					temp_arr[++k] = arr[p]; 
				} 

				break;
			}
		}
	} // end for


	for(int i=start, j =0; i<=end ; i++, j++ ){
		arr[i] = temp_arr[j];
	}

}

void split(int arr[], int start, int end){
	if( start < end ){
		int temp_end = ( start + end )/2;

		// printf("%d %d %d\n", start, temp_end, end);
		split(arr, start, temp_end);
		split(arr, temp_end+1, end);

		merge(arr, start, temp_end, end);
	}

}

int main(void){
	
	FILE* fp = fopen("input2.txt", "rt");

	int score[NUM_SCORE];
	
	for(int i =0; i<NUM_SCORE ; i++){
		fscanf(fp, "%d", &score[i]);	
	//	printf("%d\n", score[i]);
	}

	split(score, 0, NUM_SCORE-1);

	for(int i =0; i<NUM_SCORE ; i++){
		// fscanf(fp, "%d", &score[i]);	
		printf("%d\n", score[i]);
	}

	fclose(fp);
	return 0;
}