# Help regarding time complexity difference

I am confused as to what data types has to do with the time complexity of a solution.
I came across a problem:
Problem link: CodeChef: Practical coding for everyone

Solution which got TLE:-
#include <bits/stdc++.h>
using namespace std;
#define int long long

int32_t main()
{
int a;int b;cin>>a>>b;
int temp=a;
int ans=0;
while(temp<=b)
{
ans++;
temp=temp*2;
}
cout<<ans;
return 0;
}

solution which got accepted:

#include <bits/stdc++.h>
using namespace std;
#define int long long

int32_t main()
{
double a,b;
cin>>a>>b;
double ans=0,temp=a;
while(temp<=b){
ans++;
temp*=2;
}
cout<<ans;
return 0;
}

Please throw some insights as to how these solutions vary in terms of time complexity.

Anyone can find the logic behind the TLE?

Long long is slower as it requires more bits

@dhruv788 ,even after changing the data type to int ,it gives TLE.Only in case of double it is getting the solution accepted. Whats the logic behind this?
I have attached the problem link in the parent thread,test it out

https://www.codechef.com/viewsolution/46755139
using long long and float will also work

It’s easy to see how to make a solution like e.g. this one TLE:

``````1111 2147483647
``````

but I can’t see how you’d do it with e.g. this (note the - shudder - `#define int long long`), assuming of course that the constraints are correct (a fairly big assumption, as it’s a third-party contest and they didn’t manage to render them in LaTeX properly XD).

Edit:

Maybe someone should do a submission where they `assert` that 1 \le A \le B \le 10^{18}.

@akshay_012 my doubt is why does simple int gives TLE and float doesn’t?

@ssjgz Even if we assume range of A and B to be within limits,why does int gives TLE and double gives AC.
Any logic behind that?

Run the test input with the `int` solution (CodeChef: Practical coding for everyone) and find out Hint:

Print the value of `res` for each iteration of the loop.

still didn’t get ur point,can u please elaborate what test input u have used and whats the point u r trying to make by it?

Try it and see 