Javascript Solution using bfs with right node first..
\nvar findBottomLeftValue = function(root) {\n    let queue = [root];\n    let node = root;\n    while (queue.length){\n        if(!queue){\n            return;
```\nvar findBottomLeftValue = function(root) {\n    let queue = [root];\n    let node = root;\n    while (queue.length){\n        if(!queue){\n            return;\n        }\n        node = queue.pop();\n        if(node.right){\n            queue.unshift(node.right);\n        }\n        if(node.left){\n            queue.unshift(node.left);\n        }\n    }\n    return node.val;\n};\n```
['Breadth-First Search', 'JavaScript']