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  1. #include<bits/stdc++.h>
  2.  
  3. using namespace std;
  4. void kt(int l, int r)
  5. {
  6.     bool prime[r - l + 1];
  7.     memset(prime,true,sizeof(prime));
  8.     for (long long i = 2; i * i <= r; ++i)
  9.         {
  10.         for (long long j = max(i * i, (l + (i - 1)) / i  * i); j <= r; j += i)
  11.         {
  12.             prime[j - l] = false;
  13.         }
  14.     }
  15.     long long j=0,csi,csj,maxx=0,minn=1e11;
  16.      for (long long i = max(l, 2); i <= r; ++i)
  17.     {
  18.         if (prime[i - l])
  19.         {
  20.             if (j==0) j=i;
  21.             else
  22.             {
  23.                 if (i-j<minn)
  24.                 {
  25.                     minn=i-j;
  26.                     csi=i;
  27.                     csj=j;
  28.                 }
  29.                 j=i;
  30.             }
  31.         }
  32.     }
  33.     if (minn!=1e11)
  34.     {
  35.         cout<<csj<<","<<csi<<" are closest";
  36.     }
  37.     for (long long i = max(l, 2); i <= r; ++i)
  38.     {
  39.         if (prime[i - l])
  40.         {
  41.             if (j==0) j=i;
  42.             else
  43.             {
  44.                 if (i-j>maxx)
  45.                 {
  46.                     maxx=i-j;
  47.                     csi=i;
  48.                     csj=j;
  49.                 }
  50.                 j=i;
  51.             }
  52.         }
  53.     }
  54.     if (maxx!=0)
  55.     {
  56.         cout<<", ";
  57.         cout<<csj<<","<<csi<<" are most distant." <<endl;
  58.         return ;
  59.     }
  60.     cout<<"There are no adjacent primes."<<endl;
  61. }
  62. int main()
  63. {
  64.     long long a,b,t;
  65.     while(cin>>a>>b)
  66.     {
  67.         kt(a,b);
  68.     }
  69.     return 0;
  70. }
  71.  
Success #stdin #stdout 0s 4388KB
comments (?)
stdin 
Standard input is empty
stdout 
Standard output is empty
https://ideone.com/Hq3Zi4
language:
C++14 (gcc 8.3)
created:
6 years ago
visibility:
public

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