Ways to remove one element from a binary string so that XOR becomes zero | Return number of ways in which XOR become ZERO by remove 1 element ; Counting number of 0 and 1 ; If count of ones is even then return count of zero else count of one ; Driver Code
< ? php function xorZero ( $ str ) { $ one_count = 0 ; $ zero_count = 0 ; $ n = strlen ( $ str ) ; for ( $ i = 0 ; $ i < $ n ; $ i ++ ) if ( $ str [ $ i ] == '1' ) $ one_count ++ ; else $ zero_count ++ ; if ( $ one_count % 2 == 0 ) return $ zero_count ; return $ one_count ; } $ str = "11111" ; echo xorZero ( $ str ) , " STRNEWLINE " ; ? >