I have participated in a codeforce's contest for the 1st time last day. I have faced a problem [actually silly 1]. In UVa,we use generally a while loop to confirm the code will be executed for more than 1 testcases.
like
  
[code]
while(scanf("%d",&n)==1){
//code is here
}
[/code]


But in codeforces,
I got TLE,when I removed that part ,and make the code for only one testcase I got Accepted.
[when practice, I got AC with While() also]


Can anyone tell me,when I should use it or not???

thanks in advance.....