comefrom: <awangdev>852. Peak Index in a Mountain Array_1.java
code: public int peakIndexInMountainArray(int[] A) {
          int start = 1, end = A.length - 2;
          int mid = start + (end - start)/2;
          while (start + 1 < end) {
              mid = start + (end - start)/2;
              if (A[mid-1] < A[mid] && A[mid] > A[mid+1]) return mid;
              else if (A[mid-1] < A[mid+1]) start = mid;
              else if (A[mid-1] > A[mid+1]) end = mid;
          }
          return A[start] < A[end] ? end : start;
      }
masked: public int sample_funcname ( int [ ] var_0 ) {
    int var_1 = 1 , var_2 = var_0 . length - 2 ;
    int var_3 = var_1 + ( var_2 - var_1 ) / 2 ;
    while ( var_1 + 1 < var_2 ) {
      var_3 = var_1 + ( var_2 - var_1 ) / 2 ;
      if ( var_0 [ var_3 - 1 ] < var_0 [ var_3 ] && var_0 [ var_3 ] > var_0 [ var_3 + 1 ] ) return var_3 ;
      else if ( var_0 [ var_3 - 1 ] < var_0 [ var_3 + 1 ] ) var_1 = var_3 ;
      else if ( var_0 [ var_3 - 1 ] > var_0 [ var_3 + 1 ] ) var_2 = var_3 ;
    }
    return var_0 [ var_1 ] < var_0 [ var_2 ] ? var_2 : var_1 ;
  }
  