028-tree-min-value

tree min value

Write a function, treeMinValue, that takes in the root of a binary tree that contains number values. The function should return the minimum value within the tree.

You may assume that the input tree is non-empty.

test_00:

const a = new Node(3);
const b = new Node(11);
const c = new Node(4);
const d = new Node(4);
const e = new Node(-2);
const f = new Node(1);

a.left = b;
a.right = c;
b.left = d;
b.right = e;
c.right = f;

//       3
//    /    \
//   11     4
//  / \      \
// 4   -2     1

treeMinValue(a); // -> -2

test_01:

const a = new Node(5);
const b = new Node(11);
const c = new Node(3);
const d = new Node(4);
const e = new Node(14);
const f = new Node(12);

a.left = b;
a.right = c;
b.left = d;
b.right = e;
c.right = f;

//       5
//    /    \
//   11     3
//  / \      \
// 4   15     12

treeMinValue(a); // -> 3

test_02:

const a = new Node(-1);
const b = new Node(-6);
const c = new Node(-5);
const d = new Node(-3);
const e = new Node(-4);
const f = new Node(-13);
const g = new Node(-2);
const h = new Node(-2);

a.left = b;
a.right = c;
b.left = d;
b.right = e;
c.right = f;
e.left = g;
f.right = h;

//        -1
//      /   \
//    -6    -5
//   /  \     \
// -3   -4   -13
//     /       \
//    -2       -2

treeMinValue(a); // -> -13

test_03:

const a = new Node(42);

//        42

treeMinValue(a); // -> 42