could you help me get the program to loop back to asking for 2 strings and only ending if quit is input

#include

#include

#include

#include

#include

#include

#include

using namespace std;

int main(int argc, char const *argv[])

{

int pfd[2];

pipe(pfd);

char op = 'y';

char cmdn1[10][20] = {0}; // saparate it

char cmdn2[10][20] = {0}; // saparate it

char * argv1[10] ; // give it to argv

char * argv2[10] ; // give it to argv

int i , j = 0 , k = 0;

char a[20]={0};

int wordc1 = 0;

int wordc2 = 0;

string quit;

while (quit[0] != 'Q' && quit[0] != 'q')

{

string string1, string2;

cout << "enter first string ";

getline(cin, string1);

cout << "enter second string ";

getline(cin, string2);

for( i =0 ; i<10;i++)

argv1[i] = NULL; // in the starting null all pointer

k = 0, j = 0 , i = 0;

for(i=0;i <= string1.size() ; i++)

{

if(string1[i] == ' ' || string1[i] == '\0') // saparate command

{

a[j] = '\0';

strcpy(cmdn1[k++],a);

argv1[k-1] = cmdn1[k-1]; // allocate each saparate argument to argv

j = 0;

wordc1++;

memset(a,0,sizeof(a));

}

else

a[j++] = string1[i];

}

for( i =0 ; i<10;i++)

argv2[i] = NULL; // in the starting null all pointer

k = 0, j = 0 , i = 0;

for(i=0;i <= string2.size() ; i++)

{

if(string2[i] == ' ' || string2[i] == '\0') // saparate command

{

a[j] = '\0';

strcpy(cmdn2[k++],a);

argv2[k-1] = cmdn2[k-1]; // allocate each saparate argument to argv

wordc2++;

j = 0;

memset(a,0,sizeof(a));

}

else

a[j++] = string2[i];

}

if (fork() == 0)

{

// child gets here and handles "grep Villanova"

// replace standard input with input part of pipe

dup2(pfd[0], 0);

// close unused hald of pipe

close(pfd[1]);

// execute grep

execvp(argv2[0], argv2);

}

else

{

// parent gets here and handles "cat scores"

// replace standard output with output part of pipe

dup2(pfd[1], 1);

// close unused unput half of pipe

close(pfd[0]);

// execute cat

execvp(argv1[0], argv1);

}

cin.clear();

cin.ignore(255,' ');

cout << "Do you want to quit (quit/no)? "; //this part not working .

cin >> quit;

}

}