Stores the total sum of the array
total_sum = sum ; NEW_LINE i = 0 ; NEW_LINE j = n - 1 ; NEW_LINE while ( i < j - 1 ) : NEW_LINE INDENT if ( pre [ i ] == total_sum // 3 ) : NEW_LINE INDENT pos1 = i ; NEW_LINE DEDENT if ( suf [ j ] == total_sum // 3 ) : NEW_LINE INDENT pos2 = j ; NEW_LINE DEDENT if ( pos1 != - 1 and pos2 != - 1 ) : NEW_LINE DEDENT