PathSum.go

/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */

func searchTree(node *TreeNode, sum int, target int) [][]int {
    var left [][]int
    var right [][]int
    var temp []int
    var final = [][]int{}
    
    if node.Left == nil && node.Right == nil {
        if sum == target {
            return [][]int{{node.Val}}
        }
    }
    
    if node.Left != nil {
        left = searchTree(node.Left, sum + node.Left.Val, target)
    }
    
    if node.Right != nil {
        right = searchTree(node.Right, sum + node.Right.Val, target)
    }
    
    if left != nil {
        for _, arr := range left {
            temp = append([]int{node.Val}, arr...)
            final = append(final, temp)
        }
    }
    
    if right != nil {
        for _, arr := range right {
            temp = append([]int{node.Val}, arr...)
            final = append(final, temp)
        }
    }
    
    if len(final) == 0 {
        return nil
    } else {
        return final
    }
}

func pathSum(root *TreeNode, sum int) [][]int {
    if root == nil {
        return nil
    }
    
    return searchTree(root, root.Val, sum)
}