我是c ++的新手,我正在尝试在文件中对2个单词(双重和三重)进行字符串搜索,然后打印找到它们的行。有些行只有单词" double"有些人只有“#34; triple"”这个词。
代码似乎没有输出单词,它只是在循环结束时打印最后一行。
我忘了添加我需要打印找到单词的行的第一个元素,我能够找到找到单词的行,但是,它似乎不打印第一个元素文件。
这是我的代码。
int main(int argv, char *argc[]){
const string filen("test.txt");
ifstream inFile(filen.c_str());
string line = "";
char IDList[10];
string ID = "";
char* double_word = "double"; // test variable to search in file
char* triple_word = "triple";
stringstream ss;
string word = "";
unsigned int currentLine = 0;
// iterate through each line and check if the words double or triple exist.
while(getline(inFile, line)){
currentLine++;
if (line.find(double_word) != string::npos) {
cout << "found the word \"double\" on line: " << currentLine << endl;
// this part takes the input file and reads the first character of the line i.e. the ID and adds it to the IDList
// string array.
while(inFile >> IDList){
cout << "File Id: " << IDList << endl;
inFile.ignore(numeric_limits<streamsize>::max(), ' ');
for(int i=0;i<10;i++){
ss << IDList[i] << endl;
}
word = ss.str();
}
}
else if(line.find(triple_word) != string::npos){
cout << "found the word \"triple\" on line: " << currentLine << endl;
// now take the id of this file and add it to a different queue.
while(inFile >> IDList){
cout << "File Id: " << IDList << endl;
inFile.ignore(numeric_limits<streamsize>::max(), ' ');
for(int i=0;i<10;i++){
ss << IDList[i] << endl;
}
word = ss.str();
}
}
else if(line.find(double_word) && line.find(triple_word) != string::npos){
cout << "Found both words double and triple in line: " << currentLine << endl;
while(inFile >> IDList){
cout << "File Id: " << IDList << endl;
inFile.ignore(numeric_limits<streamsize>::max(), ' ');
for(int i=0;i<10;i++){
ss << IDList[i] << endl;
}
word = ss.str();
}
}
else{
cout << "neither word found, moving to next line" << endl;
}
}
inFile.close();
cout << "Id's added to the queue" << word << endl;
return 0;
}
答案 0 :(得分:1)
我认为您可以简化代码并编写类似的内容:
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <sstream>
using std::string;
using std::vector;
using std::cout;
using std::cin;
int main(int argc, char* argv[]) {
const string filen("test.txt");
std::ifstream inFile(filen.c_str());
string line;
string double_word = "double"; // test variable to search in file
string triple_word = "triple";
vector<string> IDs;
unsigned int currentLine = 0;
// iterate through each line and check if the words double or triple exist.
while(getline(inFile, line)){
currentLine++;
bool found_d_word = line.find(double_word) != string::npos;
bool found_t_word = line.find(triple_word) != string::npos;
if ( found_d_word && !found_t_word )
cout << "found the word \"double\" on line: " << currentLine << '\n';
if ( found_t_word && !found_d_word )
cout << "found the word \"triple\" on line: " << currentLine << '\n';
if ( found_d_word && found_t_word )
cout << "Found both words double and triple in line: " << currentLine << '\n';
if ( found_d_word || found_t_word ) {
std::istringstream ss{line};
string ID;
ss >> ID;
cout << "File Id: " << ID << '\n';
// my guess: store all the IDs in one vector
IDs.push_back(ID);
} else {
cout << "neither word found, moving to next line\n";
}
}
inFile.close();
return 0;
}
您的代码的一个问题是您首先读取输入文件的一行(使用getline),将其放在一个字符串中然后,当单词&#34; double&#34;或&#34;三重&#34;在字符串中找到,您尝试从文件中读取ID,同时应从同一字符串中读取它。
答案 1 :(得分:0)
试试这个,
#include "iostream"
#include "string"
#include "sstream"
#include "fstream"
using namespace std;
int main()
{
stringstream y; string x; int lc=0, id;
ifstream fin("file.txt");
while (getline(fin, x))
{
++lc;
y.str(x);
y >> id;
bool d=x.find("double")!=string::npos;
bool t=x.find("triple")!=string::npos;
if (d and t)
cout << "found words double and triple on line " << lc
<< ", id is " << id << endl;
else if (d)
cout << "found word double on line " << lc
<< ", id is " << id << endl;
else if (t)
cout << "found word triple on line " << lc
<< ", id is " << id << endl;
}
}