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This is possible because the algorithm assumes that each of the n input elements is in the range [0, k], i.e. no element is smaller than 0 nor greater than k. The input is an array A indexed from 1 to n, the output is stored in the array B also indexed from 1 to n, and the array C is used as a temporary container, indexed from 0 to k. 1 let C[0..k] be a new array 2 for i = 0 to k 3 C[i] = 0 4 for j = 1 to A.length 5 C[A[j]] = C[A[j]] + 1 6 // C[i] now contains the number of elements equal to i. 7 for i = 1 to k 8 C[i] = C[i] + C[i - 1] 9 // C[i] now contains the number of elements less than or equal to i. 10 for j = A.length downto 1 11 B[C[A[j]]] = A[j] 12 C[A[j]] = C[A[j]] - 1 Given an input array A = [5, 1, 2, 1, 5, 3], what is the status of C at the end of the algorithm? ? 1,2,3,4,4,6 ? none of the others ? 0,1,2,3,5,5 ? 4,4,5,2,0 ? 0,0,2,3,4,4

          This is possible because the algorithm assumes that each of the n input elements is in the range
[0, k], i.e. no element is smaller than 0 nor greater than k. The input is an array A indexed from 1
to n, the output is stored in the array B also indexed from 1 to n, and the array C is used as a
temporary container, indexed from 0 to k.
1 let C[0..k] be a new array
2 for i = 0 to k
3
C[i] = 0
4 for j = 1 to A.length
5
C[A[j]] = C[A[j]] + 1
6 // C[i] now contains the number of elements equal to i.
7 for i = 1 to k
8
C[i] = C[i] + C[i - 1]
9 // C[i] now contains the number of elements less than or equal to i.
10 for j = A.length downto 1
11
B[C[A[j]]] = A[j]
12
C[A[j]] = C[A[j]] - 1
Given an input array A = [5, 1, 2, 1, 5, 3], what is the status of C at the end of the algorithm?
? 1,2,3,4,4,6
? none of the others
? 0,1,2,3,5,5
? 4,4,5,2,0
? 0,0,2,3,4,4
        
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This is possible because the algorithm assumes that each of the n input elements is in the range
[0, k], i.e. no element is smaller than 0 nor greater than k. The input is an array A indexed from 1
to n, the output is stored in the array B also indexed from 1 to n, and the array C is used as a
temporary container, indexed from 0 to k.
1 let C[0..k] be a new array
2 for i = 0 to k
3
C[i] = 0
4 for j = 1 to A.length
5
C[A[j]] = C[A[j]] + 1
6 // C[i] now contains the number of elements equal to i.
7 for i = 1 to k
8
C[i] = C[i] + C[i - 1]
9 // C[i] now contains the number of elements less than or equal to i.
10 for j = A.length downto 1
11
B[C[A[j]]] = A[j]
12
C[A[j]] = C[A[j]] - 1
Given an input array A = [5, 1, 2, 1, 5, 3], what is the status of C at the end of the algorithm?
? 1,2,3,4,4,6
? none of the others
? 0,1,2,3,5,5
? 4,4,5,2,0
? 0,0,2,3,4,4

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This is possible because the algorithm assumes that each of the n input elements is in the range [0, k], i.e. no element is smaller than 0 nor greater than k. The input is an array A indexed from 1 to n, the output is stored in the array B also indexed from 1 to n, and the array C is used as a temporary container, indexed from 0 to k. Let C[0..k] be a new array. For i = 0 to k: C[i] = 0 For j = 1 to A.length: C[A[j]] = C[A[j]] + 1 // C[i] now contains the number of elements equal to i. For i = 1 to k: C[i] = C[i] + C[i-1] // C[i] now contains the number of elements less than or equal to i. For j = A.length downto 1: B[C[A[j]]] = A[j] C[A[j]] = C[A[j]] - 1
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Transcript

-
00:01 Hey, it's clarissa enumerate here.
00:02 So the algorithm only makes comparisons in the line m sub ij is defined to be min of m sub ij, comma, a, sub k.
00:20 So one comparison is made in each iteration of the three four loops.
00:24 So for i, it can take on the values from 1 to n.
00:30 So it is o.
00:32 Hey it's clarissa enumerate here so the algorithm only makes comparisons in the line m sub i j is defined to be min i can take on n values j can take on the values from i plus one to n so j can take on the value take on n minus i values which is at most n minus one values this is assuming the i is equal to n.
01:10 To 1.
01:11 So k can take on the values of 1 plus i to j.
01:15 So j can take on values j minus 1, which is at most n minus 1 values...
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