Search a Word in a 2D Grid of characters

// C++ programs to search a word in a 2D grid
#include <bits/stdc++.h>
using namespace std;

// For searching in all 8 direction
int x[] = { -1, -1, -1, 0, 0, 1, 1, 1 };
int y[] = { -1, 0, 1, -1, 1, -1, 0, 1 };

// This function searches in
// all 8-direction from point
// (row, col) in grid[][]
bool search2D(char *grid, int row, int col,
			string word, int R, int C)
{
	// If first character of word doesn't
	// match with given starting point in grid.
	if (*(grid+row*C+col) != word[0])
		return false;

	int len = word.length();

	// Search word in all 8 directions
	// starting from (row, col)
	for (int dir = 0; dir < 8; dir++) {
		// Initialize starting point
		// for current direction
		int k, rd = row + x[dir], cd = col + y[dir];

		// First character is already checked,
		// match remaining characters
		for (k = 1; k < len; k++) {
			// If out of bound break
			if (rd >= R || rd < 0 || cd >= C || cd < 0)
				break;

			// If not matched, break
			if (*(grid+rd*C+cd) != word[k])
				break;

			// Moving in particular direction
			rd += x[dir], cd += y[dir];
		}

		// If all character matched, then value of k must
		// be equal to length of word
		if (k == len)
			return true;
	}
	return false;
}

// Searches given word in a given
// matrix in all 8 directions
void patternSearch(char *grid, string word,
				int R, int C)
{
	// Consider every point as starting
	// point and search given word
	for (int row = 0; row < R; row++)
		for (int col = 0; col < C; col++)
			if (search2D(grid, row, col, word, R, C))
				cout << "pattern found at "
					<< row << ", "
					<< col << endl;
}

// Driver program
int main()
{
	int R = 3, C = 13;
	char grid[R][C] = { "GEEKSFORGEEKS",
						"GEEKSQUIZGEEK",
						"IDEQAPRACTICE" };

	patternSearch((char *)grid, "GEEKS", R, C);
	cout << endl;
	patternSearch((char *)grid, "EEE", R, C);
	return 0;
}