704. 二分查找

2024年6月5日

链接

思路：使用二分查找。

C 代码：

int search(int* nums, int numsSize, int target) {
    int left = 0, right = numsSize - 1;
    int mid = (left + right) / 2;
    while (left <= right) {
        if (target < nums[mid]) {
            right = mid - 1;
            mid = (left + right) / 2;
        } else if (target > nums[mid]) {
            left = mid + 1;
            mid = (left + right) / 2;
        } else {
            return mid;
        }
    }
    return -1;
}

改进之后的 C 代码：

int search(int* nums, int numsSize, int target) {
    int left = 0, right = numsSize - 1;
    while (left <= right) {
        int mid = (left + right) / 2;
        if (target < nums[mid]) {
            right = mid - 1;
        } else if (target > nums[mid]) {
            left = mid + 1;
        } else {
            return mid;
        }
    }
    return -1;
}

Java 代码：

class Solution {
    public int search(int[] nums, int target) {
        int left = 0, right = nums.length - 1;
        while (left <= right) {
            int mid = (left + right) / 2;
            if (target > nums[mid]) {
                left = mid + 1;
            } else if (target < nums[mid]) {
                right = mid - 1;
            } else {
                return mid;
            }
        }
        return -1;
    }
}