Call By [Value, Pointer, Reference]

void Call_By_Reference(int &n)
{
 n++;
 return;
}

void Call_By_Value(int n)
{
 n++;
 return;
}

void Call_By_Pointer(int *n)
{
 (*n)++;
 return;
}

int main()
{
 int a=0;
 Call_By_Value(a);
 printf("%d\n",a);
 Call_By_Reference(a);
 printf("%d\n",a);
 Call_By_Pointer(&a);
 printf("%d\n",a);

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