public static void main ( String [ ] args ) {
  Scanner sc = new Scanner ( System . in ) ;
  final String S = sc . next ( ) ;
  sc . close ( ) ;
  int mNum = 0 ;
  for ( char c : S . toCharArray ( ) ) {
    if ( c == 'M' ) mNum ++ ;
  }
  int [ ] m = new int [ mNum ] ;
  int at = S . length ( ) - 1 ;
  int current = 0 ;
  int mIndex = mNum - 1 ;
  while ( mIndex >= 0 ) {
    char c = S . charAt ( at ) ;
    if ( c == 'M' ) {
      m [ mIndex ] = current ;
      mIndex -- ;
    }
    else if ( c == '+' ) {
      current ++ ;
    }
    else if ( c == '-' ) {
      current -- ;
    }
    at -- ;
  }
  Arrays . sort ( m ) ;
  int ans = 0 ;
  for ( int i = 0 ;
  i < mNum / 2 ;
  i ++ ) ans -= m [ i ] ;
  for ( int i = mNum / 2 ;
  i < mNum ;
  i ++ ) ans += m [ i ] ;
  System . out . println ( ans ) ;
}

public static void main ( String [ ] args ) { Scanner sc = new Scanner ( System . in ) ; final String S = sc . next ( ) ; sc . close ( ) ; int mNum = 0 ; for ( char c : S . toCharArray ( ) ) { if ( c == ' M ' ) mNum ++ ; } int [ ] m = new int [ mNum ] ; int at = S . length ( ) - 1 ; int current = 0 ; int mIndex = mNum - 1 ; while ( mIndex >= 0 ) { char c = S . charAt ( at ) ; if ( c == ' M ' ) { m [ mIndex ] = current ; mIndex -- ; } else if ( c == ' + ' ) { current ++ ; } else if ( c == ' - ' ) { current -- ; } at -- ; } Arrays . sort ( m ) ; int ans = 0 ; for ( int i = 0 ; i < mNum / 2 ; i ++ ) ans -= m [ i ] ; for ( int i = mNum / 2 ; i < mNum ; i ++ ) ans += m [ i ] ; System . out . println ( ans ) ; }
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