comefrom: <qiyuangong>204_Count_Primes_1.java
code: public int countPrimes(int n) {
          boolean[] isPrime = new boolean[n];
          int count = 0;
          Arrays.fill(isPrime, true);
          for (int i = 2; i < n; i++) {
              if (i * i >= n)
                  break;
              if (!isPrime[i])
                  continue;
              for (int j = i * i; j < n; j += i)
                  isPrime[j] = false;
          }
          for (int i = 2; i < n; i++)
              if (isPrime[i])
                  count++;
          return count;
      }
masked: public int sample_funcname ( int var_0 ) {
    boolean [ ] var_2 = new boolean [ var_0 ] ;
    int var_4 = 0 ;
    Arrays . fill ( var_2 , true ) ;
    for ( int var_8 = 2 ;
    var_8 < var_0 ;
    var_8 ++ ) {
      if ( var_8 * var_8 >= var_0 ) break ;
      if ( ! var_2 [ var_8 ] ) continue ;
      for ( int var_9 = var_8 * var_8 ;
      var_9 < var_0 ;
      var_9 += var_8 ) var_2 [ var_9 ] = false ;
    }
    for ( int var_8 = 2 ;
    var_8 < var_0 ;
    var_8 ++ ) if ( var_2 [ var_8 ] ) var_4 ++ ;
    return var_4 ;
  }
  