Converts a string to uppercase
static String to_upper ( char [ ] str ) { for ( int i = 0 ; i < str . Length ; i ++ ) if ( ' a ' <= str [ i ] && str [ i ] <= ' z ' ) str [ i ] = ( char ) ( ( int ) str [ i ] & ( ~ ( 1 << 5 ) ) ) ; return String . Join ( " " , str ) ; }