import std.stdio, std.algorithm, std.conv, std.array, std.string;

void main()
{
    auto line = readln().strip();
    auto s = line.to!(char[]);
    for (int i = 0; i < line.length - 1; ++i) {
        int max = line[i];
        ulong pos = i;
        for (ulong j = line.length - 1; j > i; --j) {
            if (max < line[j]) {
                max = line[j];
                pos = j;
            }
        }
        if (pos != i) {
            auto tmp = s[pos];
            s[pos] = s[i];
            s[i] = tmp;
            break;
        }
    }
    writeln(s);
}