public static void main ( String [ ] args ) {
  Scanner sc = new Scanner ( System . in ) ;
  int N = sc . nextInt ( ) ;
  long [ ] a = new long [ N ] ;
  for ( int i = 0 ;
  i < N ;
  i ++ ) {
    a [ i ] = sc . nextLong ( ) ;
  }
  long [ ] acc = new long [ N + 1 ] ;
  for ( int i = 0 ;
  i < N ;
  i ++ ) {
    acc [ i + 1 ] = acc [ i ] + a [ i ] ;
  }
  Map < Long , Integer > cnts = new HashMap < > ( ) ;
  for ( int i = 0 ;
  i <= N ;
  i ++ ) {
    int cnt = cnts . containsKey ( acc [ i ] ) ? cnts . get ( acc [ i ] ) : 0 ;
    cnts . put ( acc [ i ] , ++ cnt ) ;
  }
  long ans = 0 ;
  for ( Map . Entry e : cnts . entrySet ( ) ) {
    int num = ( int ) e . getValue ( ) ;
    ans += ( long ) num * ( num - 1 ) / 2 ;
  }
  out . println ( ans ) ;
}

public static void main ( String [ ] args ) { Scanner sc = new Scanner ( System . in ) ; int N = sc . nextInt ( ) ; long [ ] a = new long [ N ] ; for ( int i = 0 ; i < N ; i ++ ) { a [ i ] = sc . nextLong ( ) ; } long [ ] acc = new long [ N + 1 ] ; for ( int i = 0 ; i < N ; i ++ ) { acc [ i + 1 ] = acc [ i ] + a [ i ] ; } Map < Long , Integer > cnts = new HashMap < > ( ) ; for ( int i = 0 ; i <= N ; i ++ ) { int cnt = cnts . containsKey ( acc [ i ] ) ? cnts . get ( acc [ i ] ) : 0 ; cnts . put ( acc [ i ] , ++ cnt ) ; } long ans = 0 ; for ( Map . Entry e : cnts . entrySet ( ) ) { int num = ( int ) e . getValue ( ) ; ans += ( long ) num * ( num - 1 ) / 2 ; } out . println ( ans ) ; }
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