Thread: ACM Problem Confusion

Hello:
I am attempting at this Online Judge problem:
http://icpcres.ecs.baylor.edu/online...m&problem=1464

The mathematics calculation part is extremely easy; but I do not understand what type of input will be given to my problem; therefore I do not know how to do this problem.
Am I expecting the input to be from a flat text file? If so; then I would need to go through every line and calculate the answer; put it into an array and output the entire array at the end... I would keep doing that until the EOF character right? How do I look for the EOF character?
Sorry for the beginner questions; but I am really confused by what this problem really wants... Any input would be greatly appreciated!

Thanks for the help guys.
However; so I am going to assume the input is from a text file... then what would the loop for the input look like? Would I use a "do-while" loop or another one? I am thinking I would do something like this:

Code:

do
  {
    /* calculate and get result */
    //put result into array
  }
while (*test for EOF*)

But the obvious questions are... how would I make the array if I have no idea how big it will be? I thought dynamic arrays did not exist in C...
Also; and what would the test for EOF look like for redirected text files?


Thanks

Didn't you ask this problem before?

Do not store the answers. Print the result as soon as it is computed.

As for the reading in of numbers: the test for EOF doesn't change depending on whether it's redirected from stdin or read using fscanf (or similar). When you have tried to read a number that isn't there, feof is set true for that file handle.

All input for those problems will be redirected from a file to stdin. A basic skeleton for a competition problem typically looks like this:

Code:

#include <stdlib.h>
#include <stdio.h>

int main(void) {
   int num, answer;

   while (1) {
      // read input
      scanf("%d", &num);

      // handle termination condition
      if (num == 0) break;

      // do calculations
      answer = num * 2;

      // print answer
      printf("%d\n", answer);
   }

   return 0;
}

To test your program, type their sample test case into a text file (input.txt), save it, and run your program like this:

prog < input.txt

Some competitions require you to print EXACTLY the right number of newline characters (meaning your last output would not have a newline after it). The Online Judge problems do not (from what I have seen), so make sure you print a single newline after every output (unless the problem states otherwise). If you fail to do this, your submission will get flagged "wrong answer", and it will probably drive you crazy.