Recursion-outputQ

Question

int boogie( int x, int y){
if(y==2)
return x;
else
return boogie(x,y-1) + x;
}
What is returned by boogie(4,6)?

//answer:20

Answer 1

Your boogie(... ) Function is recursive function and u passing two values 4 and 6 inside function body u have written if(y==2) then it will return 2 so everytime your else part will execute until this condition y==2 satisfy

in else part
return boogie (4, 6-1) + 4
Here again function called so first value not changing but second value 6 is decreasing by 1 on every call

so it will be like this

return boogie (4, 6-1) + 4
return boogie (4, 5-1) + 4 +4
return boogie (4, 4-1) + 4 +4 +4
return boogie (4, 3-1) + 4 +4 +4 +4

Now if condition will be true and return 4 so overall sum will be 20