Write a C++ program to display Pascal’s triangle using the friend function.
If we declare a function friend int show(T4Tutorials); as a friend in a class T4Tutorials then this function friend int show(T4Tutorials); can access the private and protected members of the class T4Tutorials. You must know that a global function can also be declared as a friend function of the class.
Syntax of friend function in C++
class class_name
{
…
friend return_type function_name(arguments);
…
}
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#include<iostream> using namespace std; class T4Tutorials { public: int r,s,i,j,c; public: int pattern() { cout<<"Enter number of rows"<<endl; cin>>r; } friend int show(T4Tutorials); }; int show(T4Tutorials a) { for(a.i=0;a.i<a.r;a.i++) { for(a.s=1;a.s<=a.r-a.i;a.s++) { cout<<" "; } for(a.j=0;a.j<=a.i;a.j++) { if(a.j==0||a.i==0) { a.c=1; } else { a.c=a.c*(a.i-a.j+1)/a.j; } cout<<a.c<<" "; } cout<<endl; } } int main() { T4Tutorials a; a.pattern(); show(a); } |
Output
