Codeforces 584D. Dima and Lisa Solution

Solve in  C++;

1. ///**********ALLAH IS ALMIGHTY************///
2. ///AH Tonmoy
3. ///Department of CSE,23rd Batch
4. ///Islamic University,Bangladesh
5. #include<bits/stdc++.h>
6. using namespace std;
7. bool isprime(int no)
8. {
9. int sq=sqrt(no);
10. for(int i=2; i<=sq; i++)
11. {
12. if(no%i==0)
13. {
14. return false;
15. }
16. }
17. return true;
18. }
19. main()
20. {
21. int r,f,i,j,a;
22. int n;
23. while(scanf("%d",&n)!=EOF)
24. {
25. f=0;
26. if(isprime(n))
27. {
28. cout<<"1"<<endl;
29. cout<<n<<endl;
30. }
31.  
32. else
33. {
34. for(i=n; i>1; i--)
35. {
36. if(isprime(i))
37. {
38. a=i;
39. break;
40. }
41.  
42. }
43. r=n-a;
44. if(r%2==1||r==2)
45. {
46.  
47. cout<<"2"<<endl;
48. cout<<r<<" "<<a<<endl;
49. }
50. else
51. {
52. for(i=2; i<r-1; i++)
53. {
54. for(j=r-1; j>1; j--)
55. {
56. if(isprime(i))
57. {
58. if(isprime(j))
59. {
60. if(i+j==r)
61. {
62. cout<<"3"<<endl;
63. cout<<i<<" "<<j<<" "<<a<<endl;
64. f=1;
65. break;
66. }
67. if(f==1)
68. break;
69. }
70. if(f==1)
71. break;
72. }
73. if(f==1)
74. break;
75. }
76. if(f==1)
77. break;
78.  
79. }
80.  
81. }
82.  
83. }
84. }
85. }