Help with using functions!

[iosgaming700]

Im trying to use functions inside functions... this is what i have...
void Init_Keno(int arr[], int size);
void twenty_Num(int arr[], int size);
void disp_Board(int arr[], int size);
int main()
{
srand(time(0));
cout << "Do you want to play a game? Enter y for yes and n for no." << endl;
cin >> Yes, No;
while (Yes == 'y')
{
int KenoArray[81];
Init_Keno(KenoArray, 81);


cout << endl;

twenty_Num(KenoArray, 81);

disp_Board(KenoArray, 81);
cout << "Do you want to play again? Enter y for yes and n for no." << endl;
cin >> Yes, No;
}


return 0;
}
void Init_Keno(int arr[], int size)
{
for (int i=0; i < size ; i++)
{
arr[i]=0;
}

return;
}
void twenty_Num(int arr[], int size)
{
int KenoArray[81];
Init_Keno(KenoArray, 81);

int j;
int count=0;
int ranNum;

count = 0;
while( count < 20)
{
ranNum = rand() % 80 + 1;
if (KenoArray[ranNum] == 0)
{
cout << ranNum << endl;
KenoArray[ranNum] = ranNum;
count++;
}
}

return;
}
void disp_Board(int arr[], int size)
{
int KenoArray[81];

twenty_Num(KenoArray, 81);

int i;
for (int i=1; i <=10 ; i++)
cout << setw(5) << left << KenoArray[i];
cout<< endl;
for (int i=11; i<=20; i++)
cout << setw(5) << left << KenoArray[i];
cout << endl;
for (int i=21; i<=30; i++)
cout << setw(5) << left << KenoArray[i];
cout << endl;
for (int i=31; i<=40; i++)
cout << setw(5) << left << KenoArray[i];
cout << endl;
for (int i=41; i<=50; i++)
cout << setw(5) << left << KenoArray[i];
cout << endl;
for (int i=51; i<=60; i++)
cout << setw(5) << left << KenoArray[i];
cout << endl;
for (int i=61; i<=70; i++)
cout << setw(5) << left << KenoArray[i];
cout << endl;
for (int i=71; i<=80; i++)
cout << setw(5) << left << KenoArray[i];
cout <<endl;
return;
}

[iosgaming700]

Im trying to use what i have in each funtion without typing the same code in each function.