单词替换程序demo

#include <fstream>
#include <map>
#include <string>
#include <sstream>

#include <iostream>

using namespace std;

map<string,string> buildMap(ifstream &map_file) {
 map<string, string> trans_map;
 string key;//要替换的单词
 string value;//替换后的内容
 //读取map_file文件，将单词存入key中，剩余要替换的内容存入value中
 while (map_file >> key&&getline(map_file, value)) {
  //检查是否有转换规则
  if (value.size() > 1) {
   trans_map[key] = value.substr(1);//跳过前导空格
  }
  else {
   throw runtime_error("no rule for " + key);
  }
 }
 return trans_map;
}

string transform(const string &word,const map<string,string> &m) {
 auto it = m.find(word);
 if (it!=m.cend()) {
  return it->second;
 }
 else {
  return word;
 }
}

void  WordConversion(ifstream &map_file, ifstream &input) {
 auto trans_map = buildMap(map_file);
 string text;//保存输入的每一行
 while (getline(input, text)) {
  //处理每一个单词
  istringstream stream(text);
  string word;
  bool isspace = true;//控制是否打印空格
  while (stream >> word) {
   if (isspace)
    isspace = false;
   else {
    cout << " ";
   }
   cout << transform(word, trans_map);
  }
  cout << endl;
 }
}

int main() {
 ifstream map_file("C:/Users/Administrator/Desktop/map_file.txt");
 ifstream input("C:/Users/Administrator/Desktop/input.txt");
 WordConversion(map_file, input);
 system("pause");

 return 0;
}

map_file.txt 文件

brb be right back
k okay?
y why
r are
u you
pic picture
thk thanks!
l8r later

input.txt 文件

where r u
y dont u send me a pic
k thk l8r