#include <stdio.h>
#include <string.h>
#include <math.h>
int find (int a[], int x) {
int l = 0, r = 6;
while (l < r) {
int mid = (l + r)/ 2;
if (a[mid] > x){//说明X在右侧
l = mid + 1;
}
else ////说明X在左侧
r = mid;
}
if (a[l] == x) return l;
return -1;
}
int main() {
int a[] = {85, 63, 52, 34, 25, 17, 6};
int x = 6;
int i = find (a, x);
if (i == -1) printf("没找到");
else printf("找到了,下标为%d\n", i);
return 0;
}