UVa 10443 - Rock, Scissors, Paper * (2D array manipulation)

Link: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=16&page=show_problem&problem=1384
Sol:

#include <iostream>
	using namespace std;
	class mat {
	public:
	int m, n;
	char **board;
	mat(int m, int n) {
	this->m = m;
	this->n = n;
	board = new char*[m];
	for (int i = 0; i < m; i++) {
	board[i] = new char[n];
	}
	}
	void set(int i, int j, char c) {
	board[i][j] = c;
	}
	void doTheMagic(int days) {
	char **pmat = new char*[m];
	for (int i = 0; i < m; i++) {
	pmat[i] = new char[n];
	}
	for (int i = 0; i < days; i++) {
	afterOneDay(&pmat);
	}
	for (int i = 0; i < m; i++) {
	delete [] pmat[i];
	}
	delete [] pmat;
	}
	void afterOneDay(char ***pmat) {
	for (int i = 0; i < m; i++) {
	for (int j = 0; j < n; j++) {
	(*pmat)[i][j] = getLetter(i, j, board[i][j]);
	}
	}
	char **pom;
	pom = *pmat;
	*pmat = board;
	board = pom;
	}
	char getLetter(int i, int j, char c) {
	switch(c) {
	case 'R':
	return isNearBy(i, j, 'P')?'P':'R';
	case 'P':
	return isNearBy(i, j, 'S')?'S':'P';
	case 'S':
	return isNearBy(i, j, 'R')?'R':'S';
	}
	}
	bool isNearBy(int i , int j, char c) {
	if (isOnBoard(i-1, j) && board[i-1][j] == c)
	return true;
	if (isOnBoard(i+1, j) && board[i+1][j] == c)
	return true;
	if (isOnBoard(i, j-1) && board[i][j-1] == c)
	return true;
	if (isOnBoard(i, j+1) && board[i][j+1] == c)
	return true;
	return false;
	}
	bool isOnBoard(int i, int j) {
	return i >= 0 && i < m && j >= 0 && j < n;
	}
	void print() {
	for (int i = 0; i < m; i++) {
	for (int j = 0; j < n; j++) {
	cout << board[i][j];
	}
	cout << endl;
	}
	}
	~mat() {
	for (int i = 0; i < m; i++) {
	delete [] board[i];
	}
	delete [] board;
	}
	};
	int main() {
	int tc, m, n, days;
	char c;
	cin >> tc;
	while (tc--) {
	cin >> m >> n >> days;
	mat b(m, n);
	for (int i = 0; i < m; i++)
	for (int j = 0; j < n; j++) {
	cin >> c;
	b.set(i, j, c);
	}
	b.doTheMagic(days);
	b.print();
	if (tc != 0)
	cout << endl;
	}
	}