ABC018B - 文字列の反転

問題：B - 文字列の反転

#include <algorithm>
#include <cstdio>
#include <iostream>
#include <string>
using namespace std;

#define REP(i, n) for(int i = 0 ; i < (n); ++i)

int main(void) {
    string s;
    int n, a, b;

    cin >> s;
    scanf ("%d", &n);
    REP(i, n) {
        scanf ("%d %d", &a, &b);
        reverse(s.begin() + (a - 1), s.begin() + b);
    }

    cout << s << "\n";
    return 0;
}