### Sum of nodes at k-th level in a tree represented as string

`#include <bits/stdc++.h> `
`using` `namespace` `std; `
` `
`// Function to find sum of digits `
`// of elements at k-th level `
`int` `sumAtKthLevel(string tree, ``int` `k) `
`{ `
`    ``int` `level = -1; `
`    ``int` `sum = 0;  ``// Initialize result `
`    ``int` `n = tree.length(); `
` `
`    ``for` `(``int` `i=0; i<n; i++) `
`    ``{ `
`        ``// increasing level number `
`        ``if` `(tree[i] == ``'('``) `
`            ``level++; `
` `
`        ``// decreasing level number `
`        ``else` `if` `(tree[i] == ``')'``) `
`            ``level--; `
` `
`        ``else`
`        ``{ `
`            ``// check if current level is `
`            ``// the desired level or not `
`            ``if` `(level == k) `
`                ``sum += (tree[i]-``'0'``); `
`        ``} `
`    ``} `

` `// required sum
`    ``return` `sum; `
`} `

` `// Driver program to test above
`int` `main() `
`{ `
`    ``string tree = ``"(0(5(6()())(4()(9()())))(7(1()())(3()())))"``; `
`    ``int` `k = 2; `
`    ``cout << sumAtKthLevel(tree, k); `
`    ``return` `0; `
`} `

// output=14
//description :: Given an integer %u2018K%u2019 and a binary tree in string format. Every node of a tree has value in range from 0 to 9. We need to find sum of elements at K-th level from root. The root is at level 0.

//Tree is given in the form: (node value(left subtree)(right subtree))

//Examples:

```//Input : tree = "(0(5(6()())(4()(9()())))(7(1()())(3()())))"
// k = 2
//Output : 14```
` `

```//Elements at level k = 2 are 6, 4, 1, 3
//sum of the digits of these elements = 6+4+1+3 = 14```
```//Input : tree = "(8(3(2()())(6(5()())()))(5(10()())(7(13()())())))"
//    k = 3
//Output : 9
//Elements at level k = 3 are 5, 1 and 3
//sum of digits of these elements = 5+1+3 = 9//logic ://1. Input 'tree' in string format and level k
//2. Initialize level = -1 and sum = 0
//3. for each character 'ch' in 'tree'
// 3.1  if ch == '(' then
//    --> level++
//3.2  else if ch == ')' then
//   --> level--
//3.3  else
//   if level == k then
//    sum = sum + (ch-'0')
//4. Print sum```

#### More Articles of Priya Vijayvargiya:

Name Views Likes
Sum of nodes at k-th level in a tree represented as string 243 14