Reversals

#include <iostream>
#include <string>
#include <math.h>

int main() {
	using namespace std;
	ios::sync_with_stdio(0);

	int n, m;
	cin >> n;
	cin >> m;

	char my_string[n];
	cin >> my_string;

	for (int i = 0; i < m; i++) {
		float a, b;
		cin >> a;
		cin >> b;

		for (int j = 0; j < ceil((b - a) / 2); j++) {
			char tmp = my_string[int(a + j) - 1];
			my_string[int(a + j) - 1] = my_string[int(b - j) - 1];
			my_string[int(b - j) - 1] = tmp;
		}
	}

	cout << my_string;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: TIME LIMIT EXCEEDED