Any Optimisations suggested for this code, its getting TLE in last 2 cases

#1

Ques Link: https://hack.codingblocks.com/contests/c/547/760
Code Link: https://ide.codingblocks.com/s/43745

#2

You can refer my code : https://ide.codingblocks.com/s/43930

#3

Instead of calling prime seive function again and again for each test case ,compute it once and store the values in a vector and use it for the segmented seive.

#4

Doing that also gives TLE idk why

#5

for(long long i = 2; i*i<=b;i++){ // going form 2 to root(b)

    for(long long j = a; j<=b; j++){

        if(p[i]){
            if(j==i)      // if overlapping is there ignore it
                continue;

            if(j%i==0){         // if number is not prime then set its value to false with shifting
                // a ->0.........b->b-a
                // shifted by a to left
                prime[j-a]=0;
            }
        }
    }

This part of your code is producing a TLE. Iterating from a to b will for each prime will lead to TLE.
Instead, find first divisor of p[i] that is >=a. Let this be j. Now mark j+p[i], j+2p[i], j+3p[i],… till this number is less than b.

I have used this in my approach, so try this part yourself or take help from my code.