在整形有序数组中查找想要的数字,找到了返回下标,找不到返回-1.
#include<stdio.h>
int main(){
double arr[] = { 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 };
int to_find = 7;
int left = 0;
int right = sizeof(arr) / sizeof(arr[0]) - 1;
int mid = 0;
while (left <= right){
mid = (left + right) / 2;
if (to_find < arr[mid]){
right = mid - 1;
}
else if (to_find>arr[mid]){
left = mid + 1;
}
else{
break;
}
}if (left<=right){
printf("%d\n", mid);
}
else{
printf("-1");
}
system("pause");
return(0);
}