Word Search

You are given a 2D board of characters and a string word. Return true if the word exists in the grid, where the word can be constructed from letters of sequentially adjacent cells, where adjacent cells are horizontally or vertically neighboring. The same letter cell may not be used more than once. If the word exists, print 'True', otherwise print 'False'. Example: Input: 4 4 A B C E S F C S A D E E S C S word: ABCCED Output: True