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Write a program of a Merge Sort algorithm implemented by the following pseudocode. You should also report the number of comparisons in the Merge function.
Merge(A, left, mid, right) n1 = mid - left; n2 = right - mid; create array L[0...n1], R[0...n2] for i = 0 to n1-1 do L[i] = A[left + i] for i = 0 to n2-1 do R[i] = A[mid + i] L[n1] = SENTINEL R[n2] = SENTINEL i = 0; j = 0; for k = left to right-1 if L[i] <= R[j] then A[k] = L[i] i = i + 1 else A[k] = R[j] j = j + 1Merge-Sort(A, left, right){ if left+1 < right then mid = (left + right)/2; call Merge-Sort(A, left, mid) call Merge-Sort(A, mid, right) call Merge(A, left, mid, right
In the first line n is given. In the second line, n integers are given.
In the first line, print the sequence S. Two consequtive elements should be separated by a space character.
In the second line, print the number of comparisons.
108 5 9 2 6 3 7 1 10 4
1 2 3 4 5 6 7 8 9 1034
代码如下:
#include#include #include #include using namespace std;const int maxn=500005;const int INF=0x3f3f3f3f;int n;int a[maxn];int cnt=0;void Sort (int left,int mid,int right){ int L[(maxn>>1)+10],R[(maxn>>1)+10]; int numl=mid-left; int numr=right-mid; for (int i=0;i >1; Merge (left,mid); Merge (mid,right); Sort (left,mid,right); }}int main(){ scanf("%d",&n); for (int i=0;i
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