折半排序 循环&递归 时间性能测试

#include <stdio.h>
#include <time.h>

#define COMPARE(x, y) (((x) <(y)) ?-1:((x)==(y))? 0:1)
#define MAX_SIZE 1000000
typedef struct
{
double duration;
long repetitions;
}times;

int binsearch_f(int list[],int searchnum, int left, int right);
int binsearch_r(int list[],int searchnum, int left, int right);
void timer
(int(*binsearch)(int list[],int searchnum, int left, int right)
, int list[],int searchnum, int left, int right, times *x);

int main(void)
{
static int list[MAX_SIZE];
times F,R;
printf("function           repetitions   time");

for(int n=200000; n<=MAX_SIZE; n+=200000)
{

for(int i=0; i<n; i++)
list[i]=i+1;
//		for(int k=0; k<n; k++)
//		    printf("%d ", list[k]);
//		printf("\n");

timer(binsearch_f, list, 25, 0, n,&F);
timer(binsearch_r, list, 25, 0, n,&R);

printf("\nF: array_size:%3d  %d   %6.15lf "
, n, F.repetitions, F.duration);
printf("\nR: array_size:%3d  %d   %6.15lf \n"
, n, R.repetitions, R.duration);
}

return 0;
}
int binsearch_f
(int list[],int searchnum, int left, int right)
{
int middle;
while(left <=right)
{
middle=(left+right)/2;
switch(COMPARE(list[middle], searchnum))
{
case -1: left=middle+1;
break;
case 0: return middle;
case 1: right=middle-1;
}
}
return -1;
}
int binsearch_r
(int list[],int searchnum, int left, int right)
{
int middle;
if(left <= right)
{
middle = (left+right)/2;
switch(COMPARE(list[middle], searchnum))
{
case -1: return binsearch_r
(list, searchnum, middle+1, right);
case  0: return middle;
case  1: return binsearch_r
(list, searchnum, left, middle-1);
}
}
return -1;
}

void timer
(int(*binsearch)(int list[],int searchnum, int left, int right)
, int list[],int searchnum, int left, int right, times *x)
{
x->repetitions=0;
clock_t start=clock();
do{
x->repetitions++;
binsearch(list, searchnum, left, right);
}while(clock()-start<1000);

x->duration=(double)(clock()-start/(CLOCKS_PER_SEC));
x->duration/=x->repetitions;
}