could you elaborate on how your code is supposed to work ??

more specifically what is the map <ll, ll> h doing ??

consider the test case: 1 8 8 5 6 7 1 3 2 4

you code gives: 1 8 5 6 2 7 4 3

ans 1 8 5 6 2 7 3 4

Your code is swapping them before assigning right cnt, swap(a[e],a[e-1]); cnt[a[e]]=e-1; cnt[a[e-1]]=e; First update then swap cnt[a[e]]=e-1;cnt[a[e-1]]=e;swap(a[e],a[e-1]); then second thing if say a[e] is 4 and a[e-1] is 3, then you should not swap... eg take this case: n=8, arr=[8 5 6 7 1 3 2 4] after some steps it becomes 1 8 5 6 2 7 3 4, we cannot swap 3 with 7 as that operation is already used, then your code is swapping 4 with 3, hence it gives 1 8 5 6 2 7 4 3. add a condition while(e>i && a[e-1]>a[e] && h.count(e-1)==0)