25、随机化数组.c

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

void showArray(int *a, int count);
void random_1(int *a, int count);
void random_1(int *a, int count){
	int i;
	int tmp;
	int index;

	srand(time(NULL));
	for(i = count; i > 0; i--){
		index = rand()%i;
		tmp = a[index];
		a[index] = a[i-1];
		a[i-1] = tmp;
	}

}
void showArray(int *a, int count){
	int i;

	for(i = 0; i < count; i++){
		printf("%d ", a[i]);
	}
	printf("\n");
}

int main(void){
	int a[] = {4, 6, 8, 2, 0, 7, 1,};
	int count = sizeof(a)/sizeof(int);

	showArray(a, count);
	random_1(a, count);
	showArray(a, count);

	return 0;
}