#include <iostream>
#include <algorithm>

using namespace std;

int main() {
	int n;
	cin >> n;
	char digits[10] = { 0 };
	for (int x = n, i = 9; x > 0; x /= 10, --i) {
		digits[i] = x % 10;
	}
	int maxValue = 0;
	int maxDigit;
	for (int i = 0; i < 10; ++i) {
		if (digits[i] >= maxValue) {
			maxValue = digits[i];
			maxDigit = i;
		}
	}
	int swappedDigit = -1;
	for (int i = 0; i < maxDigit; ++i) {
		if (digits[i] != 0 && digits[i] != maxValue) {
			swappedDigit = i;
			break;
		}
	}
	if (swappedDigit >= 0) {
		swap(digits[maxDigit], digits[swappedDigit]);
	}
	int x = 0;
	for (int i = 9, multiplier = 1; i >= 0; --i, multiplier *= 10) {
		x += digits[i] * multiplier;
	}
	cout << x << endl;
	return 0;
}