479. Second Max of Array【easy】

Find the second max number in a given array.

Notice

You can assume the array contains at least two numbers.

 

Example

Given [1, 3, 2, 4], return 3.

Given [1, 2], return 1.

解法一：

public class Solution {  
    /** 
     * @param nums: An integer array. 
     * @return: The second max number in the array. 
     */  
    public int secondMax(int[] nums) {  
        int first = Math.max(nums[0], nums[1]);  
        int second = Math.min(nums[0], nums[1]);  
          
        for (int i = 2; i < nums.length; i++) {  
            if (nums[i] > first) {  
                second = first;  
                first = nums[i];  
            } else if (nums[i] > second) {  
                second = nums[i];  
            }  
        }  
        return second;  
    }  
} 

从数组前两位找到first大和second大的，从i=2开始遍历，不断找当前first大和second大。