All about problems in Volume 5. If there is a thread about your problem, please use it. If not, create one with its number in the subject.
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felipej
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Posts: 2 Joined: Tue Mar 06, 2012 5:35 pm
Post
by felipej » Tue Mar 06, 2012 5:42 pm
i can't see where i'm getting wa... can any 1 help?
code:
thanks...
Last edited by
felipej on Wed Mar 07, 2012 6:27 am, edited 1 time in total.
brianfry713
Guru
Posts: 5947 Joined: Thu Sep 01, 2011 9:09 am
Location: San Jose, CA, USA
Post
by brianfry713 » Tue Mar 06, 2012 10:33 pm
14372=3+14369
Check input and AC output for thousands of problems on
uDebug !
felipej
New poster
Posts: 2 Joined: Tue Mar 06, 2012 5:35 pm
Post
by felipej » Wed Mar 07, 2012 6:27 am
thanks a lot! found bug and got AC!
Honour_00
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Posts: 4 Joined: Tue Jul 17, 2012 4:04 pm
Post
by Honour_00 » Sun Jul 22, 2012 1:46 pm
here is my code
#include <iostream>
#include <cstdio>
#include <cmath>
using namespace std;
long long pr[1000080],T;
bool isp[1000080];
void prime()
{
long long i,j;
T=0;
for(i=2;i<1000000;i++)
{
if(isp
==0)
{
for(j=i*i;j<1000000;j=j+i)
{
isp[j]=1;
}
pr[T]=i;
T++;
}
}
}
int main()
{
prime();
long long a,s,d,f,g,h,k,l;
while(scanf("%lld",&a)==1)
{
if(a==0) break;
else
{
s=1;
for(d=T-1;d>=0;d--)
{
if(pr[d]>=a) continue;
for(f=0;f<d;f++)
{
if(a==pr[d]+pr[f])
{
s=0;
printf("%lld = %lld + %lld\n",a,pr[f],pr[d]);
break;
}
}
if(s==0) break;
}
if(s==1)
{
printf("Goldbach's conjecture is wrong.\n");
}
}
}
return 0;
}
plz help
brianfry713
Guru
Posts: 5947 Joined: Thu Sep 01, 2011 9:09 am
Location: San Jose, CA, USA
Post
by brianfry713 » Tue Jul 24, 2012 12:45 am
Your code is too slow. Try stopping the inner loop when pr[d]+pr[f]>a
Check input and AC output for thousands of problems on
uDebug !
goldenbird299
New poster
Posts: 5 Joined: Sun Aug 05, 2012 6:56 am
Post
by goldenbird299 » Wed Aug 15, 2012 3:26 pm
hi everyone
can you help me with this code?
it gets RE from judge >_<
Last edited by
goldenbird299 on Thu Aug 16, 2012 7:18 am, edited 3 times in total.
brianfry713
Guru
Posts: 5947 Joined: Thu Sep 01, 2011 9:09 am
Location: San Jose, CA, USA
Post
by brianfry713 » Wed Aug 15, 2012 9:46 pm
Try 999998
Check input and AC output for thousands of problems on
uDebug !
goldenbird299
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Posts: 5 Joined: Sun Aug 05, 2012 6:56 am
Post
by goldenbird299 » Thu Aug 16, 2012 6:43 am
OMG!
what a mistake!
i thought n < 100000 !!
Thanks Brian
gr81
New poster
Posts: 46 Joined: Wed Sep 26, 2012 7:52 pm
Post
by gr81 » Mon Jan 07, 2013 6:04 pm
got AC, i forgot if ( n < 4 )...would not get processed...
kier.guevara
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Posts: 30 Joined: Thu Jul 19, 2012 11:24 pm
Post
by kier.guevara » Tue Jan 08, 2013 10:15 am
Code: Select all
#include <iostream>
#include <vector>
#include <cmath>
using namespace std;
void primeNumbers(vector <int> &prime, int n)
{
short array[1000000] = {0};
for(int i = 2; i <= sqrt(n); i++)
{
if(array[i] == 0)
{
for(int k = i+1; k < n; k++)
{
if(k % i == 0)
array[k] = 1;
}
}
}
for(int i = 3; i < n; i++)
{
if(array[i] == 0)
prime.push_back(i);
}
}
void gold(vector <int> &prime, int n)
{
for(int i = prime.size() - 1; i >= prime.size()/2; i--)
{
for(int k = 0; k <= prime.size()/2; k++)
{
if(prime[i] + prime[k] == n)
{
cout << n << " = " << prime[k] << " + " << prime[i] << endl;
return;
}
if(prime[i] + prime[k] > n)
break;
}
}
cout << "Goldbach's conjecture is wrong." << endl;
}
int main()
{
vector <int> prime;
int n;
while(cin >> n)
{
if(n == 0)
break;
primeNumbers(prime, n);
gold(prime,n);
}
return 0;
}
Im getting TLE. Is there any way I can make my code efficient?
hansyulian
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Posts: 3 Joined: Sat Dec 22, 2012 1:30 pm
Post
by hansyulian » Sun Jan 13, 2013 3:00 pm
What is wrong with my code?
Code: Select all
#include <cstdio>
#include <iostream>
#include <cstring>
using namespace std;
bool prima[1000005];
int main()
{
memset(prima,true,sizeof(prima));
prima[0] = false;
prima[1] = false;
for (long i = 2; i < 1000000; i++)
if (prima[i])
{
long j = 2*i;
while (j < 1000000)
{
prima[j] = false;
j+=i;
}
}
long n;
scanf("%ld",&n);
while (n)
{
long i = 2;
bool ada = false;
while (!ada && i < n/2)
{
if (prima[i] && prima[n-i])
{
ada = true;
printf("%ld = %ld + %ld\n",n,i,n-i);
}
i++;
}
if ( !ada) printf("Goldbach's conjecture is wrong.\n");
scanf("%ld",&n);
}
return 0;
}
brianfry713
Guru
Posts: 5947 Joined: Thu Sep 01, 2011 9:09 am
Location: San Jose, CA, USA
Post
by brianfry713 » Sun Jan 13, 2013 8:38 pm
6 = 3 + 3
Check input and AC output for thousands of problems on
uDebug !
Yusif
New poster
Posts: 27 Joined: Tue Jun 25, 2013 2:24 am
Post
by Yusif » Tue Oct 29, 2013 10:11 pm
I'm getting TL but I cant get why
Last edited by
Yusif on Tue Nov 05, 2013 10:38 pm, edited 1 time in total.