Merge_sort Merge sort C + + implementation

The following implementation of the merge sort, the first part of the Sentinel (algorithm from the introduction of the algorithm), the second part does not contain Sentinel

The first part, containing the Sentinel's merge sort:

#include <iostream>using namespace std; void mymerge (int * A, int p, int q, int r) {    int n1 = Q-p + 2;    int n2 = r-q + 1;    int l[n1];    int r[n2];    for (int i = 0; i < n 1-1; ++i)         L[i] = a[p + i];    L[n1-1] = int_max;    for (INT j = 0; j < n2-1; ++J)         R[J] = a[q + j + 1];    r[n2-1] = int_max;    INT i = 0;    Int J = 0;    for (int k = p; k <= R; ++k)       &NBSP;A[K] = L[i] < R[j]? L[i++]: r[j++];}  void merge_sort (int *a, int p, int r) {    if (R > P)     {        INT q = ( R + P)/2;        Merge_sort (A, p, q);        Merge_sort (A, q+1, R);        Mymerge (A, p, Q, R);   }} int main () {    int b[4] = {4,3,2,1};    MERGE _sort (b,0,3);    for (int i = 0; i < 4; ++i)         cout << B[i] << endl;     Retu RN 0;} -----------------------------------------------------
#include <iostream>using namespace std; void mymerge (int *a, int p, int q, int r) {    int n1 = q-p + 2;    int n2 = r-q + 1;    int l[n1];    int r[n2];    for (int i = 0; i < N1 -1; + + i)     {        L[i] = a[p + i];   }    L[n1-1] = 0;    F or (int j = 0; J < n2-1; + + j)     {        R[J] = a[q + 1 + j];   }  &NB Sp R[N2-1] = 0;    int i = 0;    int j = 0;    for (int k = p; k <= R; ++k)     {& nbsp       A[K] = L[i] > r[j]? l[i++]: r[j++];   }} void merge_descsort (int *a, int p, int R) {    if (R > P)     {& nbsp       INT q = (r + P)/2;        Merge_descsort (A, p, q);        M Erge_descsort (A, q + 1, R);        Mymerge (A, p, Q, R); &nbsP  }} int Main () {    int b[] = {1,2,3,4,5};    Merge_descsort (b, 0, 4);    for (int i = 0; I < 5; ++i)     {        cout << B[i] << endl;   }     return 0;}   

  The second part, does not contain the Sentinel's merge sort:

#include <iostream>using namespace std; void myMERGE2 (int *a, int p, int q, int r) {    int n1 = Q-p + 1;    int n2 = r-q;    int l[n1];    int r[n2];    for (int i = 0; i < N1; + +i)         L[i] = a[p + i];    for (int j = 0; J < N2; ++j)         R[J ] = a[q + 1 + j];    int i = 0;    int j = 0;    int k = p;    while (I < N1 &am p;& J < N2)         a[k++] = L[i] < R[j]? l[i++]:r[j++];    while (I < N1)         a[k++] = l[i++];    while (J < N2) &nbs P       a[k++] = r[j++];}  void merge_sort2 (int *a, int p, int r) {    if (P < r)     {        INT q = (r + P)/2;        Merge_sort2 (A, p, q);        Merge_sort2 (A, q + 1, r);  & nbsp     myMERGE2 (A, p,Q, R);   }} int main () {    int b[] = {5,4,3,2,1};    Merge_sort2 (b,0,4);    for (int i = 0; i < 5; ++i)         cout << B[i] << endl;     return 0;}

Merge_sort Merge sort C + + implementation