UVa 11221 - Magic Square Palindrome * (We deal with a matrix)

Link:https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=24&page=show_problem&problem=2162
Sol:

#include <cstdio>
	#include <stack>
	#include <cctype>
	#include <cmath>
	using namespace std;
	char s[50000];
	int main() {
	int TC, count = 0;
	scanf("%d", &TC);
	getc(stdin);
	while (TC--) {
	count++;
	char c = ' ';
	int n = 0;
	while (scanf("%c", &c), c != '\n') {
	if (isalpha(c)) {
	s[n++] = c;
	}
	}
	s[n] = '\0';
	bool palin = true;
	if ((sqrt(n) - (int) sqrt(n)) > 0)
	palin = false;
	if (palin) {
	stack<char> checker;
	int i;
	for (i = 0; i < n / 2; i++) {
	checker.push(s[i]);
	}
	if (n % 2 == 1)
	checker.push(s[i]);
	for (; i < n; i++) {
	if (checker.top() != s[i]) {
	palin = false;
	break;
	}
	checker.pop();
	}
	}
	printf("Case #%d:\n", count);
	if (palin)
	printf("%d\n", (int) sqrt(n));
	else
	printf("No magic :(\n");
	}
	return 0;
	}