Zoj1028-Flip and Shift

Q: there are black and white balls in different colors. Each ball can jump two cells each time. Can you move the ball of the same color to a continuous position? analysis: a. When the total number of balls is an odd number, the ball can be moved to A satisfactory position no matter how it moves. B. When the total number of balls is an even number, when the difference between a ball in a color of an odd or even number is less than 2, the ball can also be moved to a satisfied position. Otherwise, the ball cannot.

 #include<iostream>   #include<cstdio>   #include<cstring>   #include<cmath>   #include<algorithm>   #include<bitset>     using namespace std;    int main()  {      int Case , flag , n , num[ 50 ] , eve , odd ;      cin >> Case ;      while( Case-- )      {          cin >> n ;          eve = odd = 0 ;          for( int i = 1 ; i <= n ; ++i )          {              cin >> num[ i ] ;              if( i % 2 == 0  )                  eve += num[ i ] ;              else                  odd += num[ i ] ;          }          if( n % 2 == 1  )              flag = 1 ;          else if( odd == eve || abs( odd - eve ) == 1 )              flag = 1 ;          else              flag = 0 ;          if( flag )              cout << "YES" << endl ;          else               cout << "NO" <<endl ;      }              return 0 ;  }  #include<iostream>#include<cstdio>#include<cstring>#include<cmath>#include<algorithm>#include<bitset>using namespace std;int main(){int Case , flag , n , num[ 50 ] , eve , odd ;cin >> Case ;while( Case-- ){cin >> n ;eve = odd = 0 ;for( int i = 1 ; i <= n ; ++i ){cin >> num[ i ] ;if( i % 2 == 0  )eve += num[ i ] ;elseodd += num[ i ] ;}if( n % 2 == 1  )flag = 1 ;else if( odd == eve || abs( odd - eve ) == 1 )flag = 1 ;elseflag = 0 ;if( flag )cout << "YES" << endl ;else cout << "NO" <<endl ;} return 0 ;}