this problem different easy version in version Ujan make 2n swap in addition k le 1000 n le 50 necessary print swap you hack problem solve but hack previous problem solve problemsAfter struggle fail time Ujan decide try clean house he decide string order firstUjan distinct string s t length n consist lowercase english character he want equal since Ujan lazy perform follow operation 2n time take position j 1 le ij le n value j equal different swap character s_i t_jUjans goal string s t equal he need minimize number perform operation sequence operation length 2n shorter suitable