1 2// Licensed under the Apache License, Version 2.0 (the "License"); 3// you may not use this file except in compliance with the License. 4// You may obtain a copy of the License at 5// 6// http://www.apache.org/licenses/LICENSE-2.0 7// 8// Unless required by applicable law or agreed to in writing, software 9// distributed under the License is distributed on an "AS IS" BASIS, 10// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 11// See the License for the specific language governing permissions and 12// limitations under the License. 13// 14// Copyright 2005-2010 Google, Inc. 15// Author: jpr@google.com (Jake Ratkiewicz) 16 17#include <fst/extensions/far/compile-strings.h> 18#include <iostream> 19#include <fstream> 20 21namespace fst { 22 23// Compute the minimal length required to 24// encode each line number as a decimal number 25int KeySize(const char *filename) { 26 ifstream istrm(filename); 27 istrm.seekg(0); 28 string s; 29 int nline = 0; 30 while (getline(istrm, s)) 31 ++nline; 32 istrm.seekg(0); 33 return nline ? ceil(log10(nline + 1)) : 1; 34} 35 36} // namespace fst 37