palindrome - Best algo for finding no. of steps required to convert a sequence to a palindromic sequence -

[my first question of stackoverflow, so, hi!]

i'm not sure of rules around place, have straightforward question follows...

the sequences 23, 45, 23 , 23, 45, 56, 23, 23, 56, 45, 23 examples of palindromes. sequence 23, 45, 56 not palindrome. sequence 23, 32 not palindrome either. sequence of length 1 palindrome. given sequence of integers can broken parts such each of them palindrome. consider sequence 34,45,34,56,34. can broken 3 palindrome sequences 34, 45, 34 constituting first, 56 constituting second , 34 constituting third. can broken in 5 palindrome sequences each containing single number.

we want determine smallest number k such given sequence can broken k palindrome sequences.

#include<iostream> using namespace std;  int main() {      int n;     cin>>n;     int num[n];     for(int i=0;i<n;i++)         cin>>num[i];     int c[n];     int co=0;     for(int i=0;i<n;i++){         if(num[i]!=-1){         for(int j=i+1;j<n;++j){             if(num[i]==num[j]){                 num[i]=num[j]=-1;                 c[co]=j;                 co++;                 break;             }         }         }     }     if(n-co*2==0){         cout<<1;     }     else{         cout<<n-co*2;     }  }