#!/usr/bin/env python3
def solve(x):
    if len(x) == 1 or (x.count('0') == len(x) - 1) or (x.count(x[0]) == len(x)):
        return -1
    y = sorted(x, reverse=True)
    for i in reversed(range(len(y) - 1)):
        if y[i] != y[i + 1]:
            y[i], y[i + 1] = y[i + 1], y[i]
            break
    return ''.join(y)
print(solve(input()))