retrospect

wa.cc

 int ans=55;
 for(int tryc=0;tryc<N;++tryc){
  for(int cntr: vc){ // here I try to squeeze other ducks toward this center duck
    int t=0; //tmp ans
    printf("Try col @ %d, center @ %d\n", tryc, cntr);
    for(int row: vc){
      int up=cntr-1, down=cntr+1;
      for(int c=0;c<N;++c) if(grid[row][c]=='o'){
        t += abs(c - tryc);
        //step toward center:
        if(row>cntr){
          t += row-down;
          down += 1;
        }  
        else if(row<cntr){
          t += row-up;
          up += 1;
        }
      }
    }
    cout<<"="<<t<<endl;
    ans = min(ans, t);
  }