I heed some help with ignore(). 我有一个文本文件，里面有三行文字。
AMBITIONI DEDISSE SCRIPSISSE IUDICARETUR. ARAS\n
MATTIS IUDICIUM PURUS SIT AMET FERMENTUM. AONEC\n
SED ODIO OPERAE, EU VULPUTATE FELIS RHONCUS.\n
我需要把它读成字符串数组，像这样的句子。
AMBITIONI DEDISSE SCRIPSISSE IUDICARETUR.\n
ARAS MATTIS IUDICIUM PURUS SIT AMET FERMENTUM.\n
AONEC SED ODIO OPERAE, EU VULPUTATE FELIS RHONCUS.\n
我得到的是这样的:
AMBITIONI DEDISSE SCRIPSISSE IUDICARETUR\n
TIS IUDICIUM PURUS SIT AMET FERMENTUM\n
D ODIO OPERAE, EU VULPUTATE FELIS RHONCUS\n
有什么想法吗？
void sakiniais(){
sak=0;
ifstream fv;
fv.open("tekstas.txt");
if(fv.fail()) cout<<"Nerastas failas.";
else{
while(getline(fv,sakiniai[sak],'.')){
fv.ignore('\n');
cout<<sakiniai[sak]<<endl;
//sak++;
}
没有最初想象的那么容易。
而且，有很多可能的解决方案的原因。我向你展示了3个复杂度越来越高的解决方案，但都是使用相同的算法。
std::string请注意，第3种解决方案不需要任何循环，而且使用的是现代C++语言元素和算法。但是，没有必要在这里解释它，因为没有人会使用它。
请看。
#include <iostream>
#include <string>
#include <sstream>
#include <iterator>
#include <regex>
#include <algorithm>
std::istringstream fv{ R"(AMBITIONI DEDISSE SCRIPSISSE IUDICARETUR. ARAS
MATTIS IUDICIUM PURUS SIT AMET FERMENTUM. AONEC
SED ODIO OPERAE, EU VULPUTATE FELIS RHONCUS.
)" };
// either 1 or 2 or 3
#define COMPLEXITY 1
#if COMPLEXITY == 1
void replace(std::string& text, const std::string search, const std::string& replace) {
// Search, if the search string is in the text at all
size_t pos = text.find(search);
// Could we find it?
while (pos != std::string::npos) {
// We found it. Replace found text
text.replace(pos, search.length(), replace);
// Check, if there are more search strings in the text
pos = text.find(search, pos);
}
}
int main() {
// Here we will store the content of the complete text file
std::string text;
char c;
// Read all characters from the text file and store them in one strinf
while (fv.get(c))
text.push_back(c);
// Replace all '\n' by space
replace(text, "\n", " ");
// Replace all ". " by ".\n"
replace(text, ". ", ".\n");
// Put in stringstream for extraction with getline
std::istringstream iss(text);
// Here we will store all sentences
std::vector<std::string> sentences;
// Read all sentences from stringstream
std::string line;
while(std::getline(iss,line))
sentences.push_back(line);
// Show output
for (const std::string& s : sentences)
std::cout << s << "\n";
return 0;
}
#elif COMPLEXITY == 2
std::string& replace(std::string& text, const std::string search, const std::string& replace) {
for (size_t pos{ text.find(search) }; pos != std::string::npos; pos = text.find(search, pos)) {
text.replace(pos, search.length(), replace);
}
return text;
}
int main() {
// Here we will store the content of the complete text file
std::string text;
// Read all characters from the text file and store them in one string
for (char c{}; fv.get(c); text.push_back(c)) ; // Empty loop body
// Replace all '\n' by space and replace all ". " by ".\n"
replace(replace(text, "\n", " "), ". ", ".\n");
// Put in stringstream for extraction with getline
std::istringstream iss(text);
// Here we will store all sentences
std::vector<std::string> sentences;
// Read all sentences from stringstream
for (std::string line; std::getline(iss, line); sentences.push_back(line)); // Empty body
// Show output
for (const std::string& s : sentences) std::cout << s << "\n";
return 0;
}
#elif COMPLEXITY == 3
std::regex dotSpace(R"(\. )");
int main() {
// Read the complete text file into one string
std::string text(std::istreambuf_iterator<char>(fv), {});
// Replace all '\n' by space andf replace all ". " by ".\n"
text = std::regex_replace(std::regex_replace(text, std::regex("\n"), " "), dotSpace, ".\n");
// Get sentences
std::vector<std::string> sentences(std::sregex_token_iterator(text.begin(), text.end(), dotSpace, -1), {});
// Show debug output
std::copy(sentences.begin(), sentences.end(), std::ostream_iterator<std::string>(std::cout);
return 0;
}
#endif
这里有一种方法，用代码中的注释来解释步骤。
#include <algorithm> // replace_copy
#include <iostream>
#include <iterator> // istreambuf_iterator, back_inserter
#include <string>
#include <vector>
#include <sstream> // istringstream for demo
std::vector<std::string> sakiniais(std::istream& fv) {
std::vector<std::string> retval;
std::string all;
// copy chars from the istream "fv" into the string "all", replacing '\n' with ' '
std::replace_copy(
std::istreambuf_iterator<char>(fv), std::istreambuf_iterator<char>{},
std::back_inserter(all), '\n', ' ');
// find '.' and store substrings in the vector<string> "retval"
for(size_t begin=0, end = all.find(".");
end < all.size();
begin = end, end = all.find(".", begin))
{
++end; // include '.' in substring
// store substring
retval.emplace_back(all.substr(begin, end - begin));
// skip space following a '.'
if(end < all.size() && all[end] == ' ') ++end;
}
return retval;
}
int main () {
std::istringstream file(
"AMBITIONI DEDISSE SCRIPSISSE IUDICARETUR. ARAS\n"
"MATTIS IUDICIUM PURUS SIT AMET FERMENTUM. AONEC\n"
"SED ODIO OPERAE, EU VULPUTATE FELIS RHONCUS.\n"
);
auto strs = sakiniais(file);
for(const std::string& s : strs) {
std::cout << '>' << s << "<\n"; // show string enclosed with '>' and '<'
}
}
输出。
>AMBITIONI DEDISSE SCRIPSISSE IUDICARETUR.<
>ARAS MATTIS IUDICIUM PURUS SIT AMET FERMENTUM.<
>AONEC SED ODIO OPERAE, EU VULPUTATE FELIS RHONCUS.<