[算法] 剑指offer2 golang 面试题12：左右两边子数组的和相等

题目1:

思路1:

//思路: 
//1.记录总数 sum
//2.遍历元素计算 sum - nums[i] - leftSum == leftSum ,return i 

代码

func pivotIndex(nums []int) int {
    
    //start: 13.16 end: 13.22
    //思路: 
    //1.记录总数 sum
    //2.遍历元素计算 sum - nums[i] - leftSum == leftSum ,return i 

    //参数处理
    if len(nums) == 0 {
    
        return -1
    }

    //1.记录总数 sum
    sum := 0 
    for i := 0; i < len(nums); i++{
    
        sum += nums[i]
    }

    //2.遍历元素求中心点
    leftSum := 0 
    for i := 0; i < len(nums); i++{
    
        //(1) 判断
        if sum - nums[i] - leftSum == leftSum{
    
            return i
        }
        //判断失败
        leftSum += nums[i]
    }

    return -1
}

测试