public class Solution{
public int binarySearch(int[] nums, int target){
if(nums == null && nums.length == 0)return -1;
int start = 0;
int end = nums.length - 1;
int mid;
while(start + 1 < end){
mid = start + (end - start) / 2;
if(nums[mid] > target){
end = mid;
}else if(nums[mid] < target){
start = mid;
}else{
end = mid;
}
}
if(nums[start] == target){
return start;
}
if(nums[end] == target){
return end;
}
return -1;
}
}