dush1729's blog

How to take fast I/O in C++?
By dush1729, history, 9 years ago, In English

How to take fast I/O in C++? I am solving a problem where number of test cases can be 10^6 so i guess fast I/O will help to speed up my solution.

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9 years ago, # |
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Check out these links :

https://algocoding.wordpress.com/2015/04/23/fast-io-methods-for-competitive-programming/ http://codeforces.net/blog/entry/6251

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    9 years ago, # ^ |
      Vote: I like it +3 Vote: I do not like it

    +1 but sometimes it's not enough

    Another possible way is to implement your own reader for integer/real/signed types using getchar():

    int next_int() {
  char c;
  do { c = getchar(); } while( c != '-' && !isdigit(c) );
  bool neg = (c == '-');
  int result = neg ? 0 : c - '0';
  while( isdigit(c = getchar()) )
    result = 10 * result + (c - '0');
  return neg ? -result : result;
}

    In most cases coders use it to get top1 by execution time))

    But in case N = 10^6 it may be useful to beat TL with solution that wasn't intended by jury.

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      9 years ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Thanks it did reduce my time but still TLE. I guess i have to improve my algo.

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