#ifdef Your-pc name endif

#ifndef ONLINE_JUDGE

freopen(“input.txt”, “r”, stdin);

freopen("output.txt", "w", stdout);

freopen(“error.txt”, “w”, stderr);

#endif
but i saw some people use
#ifdef some_name

freopen(“input.txt”, “r”, stdin);

freopen("output.txt", "w", stdout);

freopen(“error.txt”, “w”, stderr);

#endif
can someone please tell me how to convert it this way so my input will be taken from input file and output will be given output.txt ?

Hi, your solution to the problem DLTNODE is among the leaked solutions as mentioned in this blog