Hack 'n' Slash BWT Reverser

#include <cstdlib>
#include <cstdio>

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

string decodeBWT(const string &input);

int main()
{
    string transformed =
        "SGGCSNTSSSFEESRWOTOSOYGL"
        "LESMDETNOEDRTSOOOTSTGERO"
        "AFFESAEEENTETEONEYRTGDTY"
        "EDNEESYEYTGEDNRLRIIETEST"
        "RSYEGUERRE.OMMM.MC...EGR"
        "RW.RFHWWE.HHMRMCHHHFWW.."
        ".A.M...IIE.SSNEEEEIARNN."
        "..HHLWHKHNMLHRNKSVRLRHWV"
        "DMLBDVRTHFBTBEERHERVDHLD"
        "HVDTGSYMN.OOO...N...SNSR"
        ".NNNNONNEAAAAOII.TW...TT"
        "TTTTWWTTTTTTP..GG.FFLW.."
        "EHVHNTTT.H.DD..RW.IALLUA"
        "ZZB.E.OIPB..BEAANRI...RR"
        "UO.OE..OEEOOUAOOOO.OIIOI"
        "IIIAOA.OAAAATTSDGSTTTL.."
        ".LNFSSII.PW..CL.IFEVFFFP"
        "LN.YH.MCCRAU....EEELEAEO"
        "TTTGUOUUEE..EOOOORUKAAEY"
        "ESIILAINWIIUSNN.L..EOOAU"
        "..SOUIAASASUEIUNSI..$..."
        ".O.YE.IAAA.....X...OFTF."
        "GGSBAJOOBPPAAOOOAAE....L"
        "........OEMLMBAH..ANZZUU";

    string result = decodeBWT(transformed);

    cout << result << endl;

    system("pause");
    return 0;
}

string decodeBWT(const string &input)
{
    // Sanity check
    if(input == "") return "";

    // Create empty table
    vector<string> table(input.length(), "");

    // For every character in the string
    for(size_t i=0; i<input.length(); i++)
    {
        // Insert the character into each row at the front
        for(size_t j=0; j<table.size(); j++)
        {
            table[j] = input.substr(j, 1) + table[j];
        }

        // Sort the rows (lexicagraphic sort by strings)
        sort(table.begin(), table.end());
    }

    // Find the row that starts with '$' and return that row (with the '$' removed)
    for(size_t i=0; i<table.size(); i++)
    {
        if(table[i].at(i) == '$') return table[i].substr(1);
    }

    // In case it didn't find one
    return "?";
}