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Can someone please tell me why my initial attempt timeouts? Here, a histogram array was used to construct a cumulative frequency array of the elements, which was then used as the keys for the correct positions of the numbers in the original array (similar to the Minimum Swaps 2 problem at https://www.hackerrank.com/challenges/minimum-swaps-2/ ):

deflilysHomework(arr):arr_original=arr.copy()b=[None]*(max(arr)+1)l=len(arr)k=(max(arr))hist=(k+1)*[0]#indicesrunsfrom0tomax(array)inclusiveforiinarr:hist[i]=1#Initialfrequencyarray,jthvalueofcountisthefrequencyofnumberjcumfreq=(k+1)*[0]cumfreq[0]=hist[0]invcumfreq={}forjinrange(1,k+1):cumfreq[j]+=cumfreq[j-1]+hist[j]ifnot(cumfreq[j]ininvcumfreq):invcumfreq[cumfreq[j]]=j## Create an array to get the inverse cumulative frequencies array:counter1=0forj,vinenumerate(arr_original):b[v]=jforjinrange(l):ifcumfreq[arr[j]]-1!=j:old=arr[j]#oldarr[j]arr[j],arr[b[invcumfreq[j+1]]]=arr[b[invcumfreq[j+1]]],arr[j]#arr[j],arr[b[cumfreq.index(j+1)]]=arr[b[cumfreq.index(j+1)]],arr[j]b[old],b[arr[j]]=b[arr[j]],b[old]counter1+=1else:continuearr=arr_original.copy()##Reset the b-array of indices!!forj,vinenumerate(arr_original):b[v]=jcounter2=0forjinrange(0,l):ifcumfreq[arr[j]]!=l-j:old=arr[j]#oldarr[j]arr[j],arr[b[invcumfreq[l-j]]]=arr[b[invcumfreq[l-j]]],arr[j]#arr[j], arr[b[revfreq.index(l-j)]] = arr[b[revfreq.index(l-j)]], arr[j] b[old],b[arr[j]]=b[arr[j]],b[old]counter2+=1else:continuereturncounter1#(min(counter1,counter2))

## Lily's Homework

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Correction:

Tried and tested - passes all cases.

Can someone please tell me why my initial attempt timeouts? Here, a histogram array was used to construct a cumulative frequency array of the elements, which was then used as the keys for the correct positions of the numbers in the original array (similar to the Minimum Swaps 2 problem at https://www.hackerrank.com/challenges/minimum-swaps-2/ ):