学习记录2

搜索算法 - 二分搜索
public class BinarySearch {
public static int binarySearch(int[] arr, int target) {
int left = 0;
int right = arr.length - 1;
while (left <= right) {
int mid = left + (right - left) / 2;
if (arr[mid] == target) {
return mid;
} else if (arr[mid] < target) {
left = mid + 1;
} else {
right = mid - 1;
}
}
return -1;
}

public static void main(String[] args) {
    int[] arr = {10, 20, 30, 40, 50};
    int target = 30;
    int result = binarySearch(arr, target);
    if (result != -1) {
        System.out.println("元素 " + target + " 在数组中的索引是: " + result);
    } else {
        System.out.println("元素 " + target + " 不在数组中。");
    }
}

}