Is there a way to combine incrementing and decrementing for loops?

Question

int j = 0;
for (int i = 1; i < 4; i++)
{
  if ((columnIndex + i) > 6 || this.isWinningCondition(columnIndex, i, j, colSlot, isRed))
     {
         break;
     }
  else
     {
        pieces++;
     }
}
for (int i = -1; i > -4; i--)
  {
    if ((columnIndex + i) < 0 || this.isWinningCondition(columnIndex, i, j, colSlot, isRed))
    {
      break;
    }
    else
    {
       pieces++;
    }
}

Basically, it is apart of a Connect4 program that searches for three in a row on the left and right side of a specific column (in this case, it is searching for horizontal wins), hence the incrementing (for the right side) and the decrementing (for the left side) for loops. Is there a way I can combine these for loops into one, so I don't have to repeat myself?

Answer 1

If your MaxValue ( 4 )is always the same for both for loop, you can always do :

for( int i = 1; i < 4; ++i)
{
   //verify i version 1
   int i2 = i * -1;
   // verify i2 version 2
}

Answer 2

Try the mixed for loop.

for(int i = 0, j = 4; i <= 4 && j >=0; i ++, j --)
{
 System.out.println(i + " " + j);
}

Output:
0 4
1 3
2 2
3 1
4 0