I used to work as research assistant to my professor. I was doing a problem on facility layout in which i had to do many combinations of numbers like 20 numbers.
Initially it was easy as i did it with 4 digits like 1,2,3,4 so i could convert them to single digit 1*1000+2*100+3*10+4*1=1234. But for a 20 digit number it became cumbersome for me, so i decided to use strings. I researched the whole google to solve this problem, atlast i got the solution
using namespace std;