（非函数方法）查找有序数组中x的位置（二分/折半）

#include<stdio.h>

int main() {
  int x = 0;
  int arr[] = { 1,2,3,4,5,6,7,8,9,10 };
  int max = sizeof(arr) / sizeof(arr[0]);
  int right = max - 1;
  int left = 0;
  printf("请输入1--10内要查询的数字：");
  scanf_s("%d", &x);

  while (left <= right) {
    int mid = (right + left) / 2;
    if (arr[mid] == x) {
      printf("%d在该数组中的第%d个位置。", x, mid + 1);
      break;
    }
    else if (arr[mid] > x) {
      right = mid - 1;
    }
    else {
      left = mid + 1;
    }
  }
  if (right < left) {
    printf("未找到概数。");
  }
  return 0;
}