OJ Board

I solved it, no need to find solutions, just count them

I got TLE because my factor funtion is too slow. Are there any fast factorization algorithms for this problem? :roll: :cry:
long Sum(long n, long a[]) /* a[] stores primes from 2 to 2221 */
{
long r = 0, i = 0;
while(n > 1)
{
if(isPrime(n,a))
{
r += n;
break;
}
while(n%a[i])
i++;
while(n ...

I get TLE on this problem :oops:.
#include<stdio.h>
#include<math.h>

main()
{
long long n, i, j, k, r, t;
while(1)
{
scanf("%lld",&n);
if(!n) break;
k = 4*n-3; i = 3; j = 2*n;
r = 1; t = sqrt(k);
while(i <= t)
{
if(j%i == 0)
{
r++;
// printf("%lld %lld\n",j/i,(i+1)/2);
}
i+=2; j ...

I know how to use fread() but I don't know how to parse input efficiently (I use strtok() and atoi() to get input numbers). Would anyone please help me

@ Rujialiu
I found that using fread/fwrite can get I/O much faster but I don't know how to use them
BTW, this is a nice problem. I think it can't be solve without using suitable data structure

I've the same question as gtcoder (post above)

here is my NOD funtion
long NOD(long n, long a[])
{
long r=1, i=0, j;
while(n>1)
{
if(isprime(n)) //if n is a prime number
{
r*=2;
break;
}
while(n%a[i]!=0)
i++;
j=0;
while(n%a[i]==0)
{
n/=a[i];
j++;
}
r*=(j+1);
}
return r;
}
I store prime numbers from 2 to sqrt(n) in the array ...

after viewing Imti's code I fixed my output from O(n/2) to O(1) and got AC in 1.7 secs . Now I'm thinking another algo to decrease my running time .

hey Imti your algo is the same as mine. I remember it took nearly 2 seconds to precaculate all NOD of all number from 1 to 1e6, so you may not have enough time to output your result

This problem is pretty similar to problem 294 - Divisors. I tried to find NOD (number of divisors) of all number in a certain range or precaculate NOD of all number from 1 to 1000000 but got TLE. Is there any better method to solve this problem? Please help

hello everyone, sorry for creating this thread if you think it's useless :D
I had got TLE in this problems many times and after 6 tries I got AC in 0.104 sec using my struct :D . But I found some guys got AC in about 0.08 or even 0.03 ~ 0.05 :o . I tried coding like this and send to judge to find ...

I only need to find all divisor of input number n in the range [1,(int)sqrt(n)) and for each divisor I print the answer :D
for example, there are 2 divisors of 16 in the range [1,4) so output 2 numbers :D
Moreover, I didn't use long long and long double, long is enough :D and your code is much ...

yan yan wrote:first, you must

Code: Select all

scanf("%d",&k);getchar();

indeed

Code: Select all

scanf("%d\n",&k);

second, the last character can be space. It's possible

Thank you very much, I got A.C
anyway, I tried to use fflush(stdin) instead of getchar() but it didn't work

I've got W.A on this problem no matter how I fixed my code . Please help me always have problems with string processing...

I also got W.A many times because I forgot to add \n in the line n is number of test cases.
Also remember not to print a blank line in the last test case.
Hope this help