If I define an array as arr[n*(n+1)/2], for numbers 5 and larger, the program either crashes or shows an error.
But if I take a variable p,store the value in it and define the array as arr[p], I don’t get any error.
Why is this so?
Also, in the fibonacci pattern, if I want to input 10 rows, why are there some numbers negative in 10th row?
Hi Rohan
In the first part, your question is little ambiguous. I guess if you store 5 in n i.e n=5 and then make arr[n*(n+1)/2],the program should work.
This is what you are trying to ask?
Not exactly.
I first asked the user to input the value of n, so we now have a definite value of n. Now I defined an array as arr[n*(n+1)/2] . It works fine for smaller values of n, but say for n = 5 or greater, the program crashes or shows an error.
Now, if I take a variable p as p=n*(n+1)/2 and define the array as arr[p] it works fine even for larger values of n.
What difference does calculating n*(n+1)/2 separately make?
Hi
#include<bits/stdc++.h>
using namespace std;
int main()
{
int n;
cout<<"Enter number: ";
cin>>n;
int arr[(n*(n+1))/2];
for(int i=0;i<(n*(n+1))/2;i++)
cin>>arr[i];
cout<<endl;
for(int i=0;i<(n*(n+1))/2;i++)
cout<<arr[i];
}
I tried this,works for me for larger values of n also
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