merge.c

implementation of merge sort algorithm and its computational cost. it is testing on arrays of lenght

#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <sys/times.h>

//Funcion merge
//one more time
void merge(int A[],int p, int q, int r)
{	//printf("merge p: %d \n ",p); 	
	int n1,n2,i,j,k;
	n1=q-p+1;
	n2=r-q;
	int L[n1+1];
	int R[n2+1];

	for(i=0;i<n1;i++)
		L[i] = A[p+i];
	for(j=0; j<n2;j++)
		R[j] = A[q+1+j];

	L[n1]=1000000; //coloco un flag tiende a inf
	R[n2]=1000000;

	i=0;
	j=0;

	for(k=p; k<=r; k++){

		if (L[i] <= R[j])
		{ 
			A[k]=L[i];
			i=i+1;
		}
		else
		{
		A[k]=R[j];
		j=j+1;
		}  


	}
}

//Funcion merge_sort

void merge_sort(int A[], double p, double r)
{
double q;
	if (p < r)
	{//printf("valor de q: %.1lf \n",q);
	q=floor((p+r)/2.0);
	merge_sort(A,p,q);//printf("primer p: %.1lf, q: %.1lf, r: %.1lf \n ",p,q,r);
	merge_sort(A,q+1.0,r);//printf("segundo q+1: %.1lf, r: %.1lf \n ",q,r);
	merge(A,(int)p,(int)q,(int)r); //printf("tercer p: %.1lf, q: %.1lf, r:%.1lf \n ",p,q,r);
	//printf("r: %.1lf \n ",r);
	}
	//printf("p: %.d \t ",p);
}



int main(){
int i, j;
//int B[]={7,9,0,1,2,3,3,5,8,4};

int tam=50;
int B[tam];
////Generando el arreglo

srand(time(NULL));
for (i = 0; i < tam; i ++) {
	B[i]=rand()%100;
printf("%d =>",B[i]);}
printf("ordenamiento **************************** \n");     
merge_sort(B,0.0,(double)(tam-1));

for(i=0;i<tam-1;i++)
printf("%d =>",B[i]);
printf("\n");
//printf ("Tiempo Ordenamiento: \n");
//printf("%.9f seconds\n", (long double)(stop_time.tms_utime-start_time.tms_utime)/1000.0f );

return 0;
}