Use the variable closer to its use

Its good programming practice to define the variable closer to its use.
Eg. In cpp, this is better code:
for(int i = 0; i{…}

rather than
int i;
…
…
for(i=0;i

See also

• For a Given node of a binary tree, print the K distance nodes.
• Find the distance between 2 nodes in Binary Tree
• Find the distance between 2 nodes in Binary Tree
• Program to count leaf nodes in a binary tree
• Friend Circle - Hackerrank