I need a regex to find anything except this String
example data is:
this is one line with this string only this should not match
this is another line but has no string in
this String is another
and then this line should match also
I want to find and highlight the entire line, so the line
this is one line with this string is the only one that will be selected.
I tried ^(?!(this String)$) but this find zero length match, so not much help, I tried adding .* in various places but don't understand how to do this.
Chances are that you don't need regex for this task at all. Look at these two pieces of code:
std::regex pattern("^((?!this string).)*$");
while (std::getline(infile, chkme)) {
if (std::regex_match(chkme,pattern)) {
std::cout << "Not found! " << chkme;
}}
and
std::string pattern = "this string";
while (std::getline(infile, chkme)) {
if (chkme.find(pattern) == string::npos) {
std::cout << "Not found! " << chkme;
}}
Related
So, I would like to change all words in a string except one, that stays in the middle.
#include <boost/algorithm/string/replace.hpp>
int main()
{
string test = "You want to join player group";
string find = "You want to join group";
string replace = "This is a test about group";
boost::replace_all(test, find, replace);
cout << test << endl;
}
The output was expected to be:
This is a test about player group
But it doesn't work, the output is:
You want to join player group
The problem is on finding out the words, since they are a unique string.
There's a function that reads all words, no matter their position and just change what I want?
EDIT2:
This is the best example of what I want to happen:
char* a = "This is MYYYYYYYYY line in the void Translate"; // This is the main line
char* b = "This is line in the void Translate"; // This is what needs to be find in the main line
char* c = "Testing - is line twatawtn thdwae voiwd Transwlate"; // This needs to replace ALL the words in the char* b, perserving the MYYYYYYYYY
// The output is expected to be:
Testing - is MYYYYYYYY is line twatawtn thdwae voiwd Transwlate
You need to invert your thinking here. Instead of matching "All words but one", you need to try to match that one word so you can extract it and insert it elsewhere.
We can do this with Regular Expressions, which became standardized in C++11:
std::string test = "You want to join player group";
static const std::regex find{R"(You want to join (\S+) group)"};
std::smatch search_result;
if (!std::regex_search(test, search_result, find))
{
std::cerr << "Could not match the string\n";
exit(1);
}
else
{
std::string found_group_name = search_result[1];
auto replace = boost::format("This is a test about %1% group") % found_group_name;
std::cout << replace;
}
Live Demo
To match the word "player" I used a pretty simply regular expression (\S+) which means "match one or more non-whitespace characters (greedily) and put that into a group"
"Groups" in regular expressions are enclosed by parentheses. The 0th group is always the entire match, and since we only have one set of parentheses, your word is therefore in group 1, hence the resulting access of the match result at search_result[1].
To create the regular expression, you'll notice I used the perhaps-unfamiliar string literal syntaxR"(...)". This is called a raw string literal and was also standardized in C++11. It was basically made for describing regular expressions without needing to escape backslashes. If you've used Python, it's the same as r'...'. If you've used C#, it's the same as #"..."
I threw in some boost::format to print the result because you were using Boost in the question and I thought you'd like to have some fun with it :-)
In your example, find is not a substring of test, so boost::replace_all(test, find, replace); has no effect.
Removing group from find and replace solves it:
#include <boost/algorithm/string/replace.hpp>
#include <iostream>
int main()
{
std::string test = "You want to join player group";
std::string find = "You want to join";
std::string replace = "This is a test about";
boost::replace_all(test, find, replace);
std::cout << test << std::endl;
}
Output: This is a test about player group.
In this case, there is just one replace of the beginning of the string because the end of the string is already the right one. You could have another call of replace_all to change the end if needed.
Some other options:
one is in the other answer.
split the strings into a vector (or array) of words, then insert the desired word (player) at the right spot of the replace vector, then build your output string from it.
When running this block of code, the whole file is outputted when I just want the specific line that includes the word. e.g looking for the word paris and displaying all lines instead of specific ones.
I have already tried get line, tweet, but that isn't working, I feel this is part of the problem but i'm not sure.
void choice1() {
string tweet;
ifstream infile;
infile.open("sampleTweets.csv");
if (infile.good()) {
while (!infile.eof()) {
getline(infile,tweet);
if (tweet.find("Paris") != tweet.length()) {
cout << "Found Paris in the line" << tweet << endl;
}
}
}
}
Would like it to output the lines that contain that word not all of the lines in the file, but at the moment it is just repeating the text o every line as if the word had been found.
The standard says find method returns npos if not found. You may refer this.
So the condition line should be:
if (tweet.find("Paris") != string::npos) {
The correct usage is shown below:
if (tweet.find("Paris") != std::string::npos) {
}
Please refer to the correct usage here.
This question already has answers here:
How do I iterate over the words of a string?
(84 answers)
Closed 6 years ago.
My homework is as follows:
Step Two - Create a file called connections.txt with a format like:
Kelp-SeaUrchins
Kelp-SmallFishes
Read these names in from a file and split each string into two (org1,org2). Test your work just through printing for now. For example:
cout << “pair = “ << org1 << “ , “ << org2 << endl;
I am not sure how to split the string, that is stored in a vector, using the hyphen as the token to split it. I was instructed to either create my own function, something like int ind(vector(string)orgs, string animal) { return index of animal in orgs.} or use the find function.
Here is one approach...
Open the file:
ifstream file{ "connections.txt", ios_base::in };
if (!file) throw std::exception("failed to open file");
Read all the lines:
vector<string> lines;
for (string line; file >> line;)
lines.push_back(line);
You can use the regex library from C++11:
regex pat{ R"(([A-Za-z0-9]+)-([A-Za-z0-9]+))" };
for (auto& line : lines) {
smatch matches;
if (regex_match(line, matches, pat))
cout << "pair = " << matches[1] << ", " << matches[2] << endl;
}
You will have to come up with the pattern according to your needs.
Here it will try to match for "at least one alphanumeric" then a - then "at least one alphanumeric".
matches[0] will contain the whole matched string.
matches[1] will contain first alphanumeric part, i.e. your org1
matches[2] will contain second alphanumeric part, i.e. your org2
(You can take them in variables org1 and org2 if you want.)
If org1 and org2 don't contain any white spaces, then you can use another trick.
In every line, you can replace - with a blank.(std::replace).
Then simply use stringstreams to get your tokens.
Side note: This is just to help you. You should do your homework on your own.
I have a huge file of Japanese example sentences. It's set up so that one line is the sentence, and then the next line is comprised of the words used in the sentence separated by {}, () and []. Basically, I want to read a line from the file, find only the words in the (), store them in a separate file, and then remove them from the string.
I'm trying to do this with regexp. Here is the text I'm working with:
は 二十歳(はたち){２０歳} になる[01]{になりました}
And here's the code I'm using to find the stuff between ():
std::smatch m;
std::regex e ("\(([^)]+)\)"); // matches things between ( and )
if (std::regex_search (components,m,e)) {
printToTest(m[0].str(), "what we got"); //Prints to a test file "what we got: " << m[0].str()
components = m.prefix().str().append(m.suffix().str());
//commponents is a string
printToTest(components, "[COMP_AFTER_REMOVAL]");
//Prints to test file "[COMP_AFTER_REMOVAL]: " << components
}
Here's what should get printed:
what we got:はたち
[COMP_AFTER_REMOVAL]:は 二十歳(){２０歳} になる[01]{になりました}
Here's what gets printed:
what we got:は 二十歳(はたち
[COMP_AFTER_REMOVAL]:){２０歳} になる[01]{になりました}
It seems like somehow the は is being confused for a (, which makes the regexp go from は to ). I believe it's a problem with the way the line is being read in from the file. Maybe it's not being read in as utf8 somehow. Here's what I do:
xml_document finalDoc;
string sentence;
string components;
ifstream infile;
infile.open("examples.utf");
unsigned int line = 0;
string linePos;
bool eof = infile.eof();
while (!eof && line < 1){
getline(infile, sentence);
getline(infile, components);
MakeSentences(sentence, components, finalDoc);
line++;
}
Is something wrong? Any tips? Need more code? Please help. Thanks.
You forgot to escape your backslashes. The compiler sees "\(([^)]+)\)" and interprets it as (([^)]+)) which is not the regex you wanted.
You need to type "\\(([^)]+)\\)"
I am trying to write a little program that will load in a file, compare each line with a specific array of words, and if that line has any of those words in it then I want to "print" that line out to a file.
My current code is:
int main()
{
string wordsToFind[13] =
{"MS SQL", "MySQL", "Virus", "spoof", "VNC", "Terminal", "imesh", "squid",
"SSH", "tivo", "udp idk", "Web access request dropped", "bounce"};
string firewallLogString = "";
ifstream firewallLog("C:\\firewalllogreview\\logfile.txt");
ofstream condensedFirewallLog("C:\\firewalllogreview\\firewallLog.txt");
if(firewallLog.fail())
{
cout << "The file does not exist. Please put the file at C:\\firewalllogreview and run this program again." << endl;
system("PAUSE");
return 0;
}
while(!firewallLog.eof())
{
getline(firewallLog, firewallLogString);
for(int i = 0; i < 13; i++)
{
if(firewallLogString == wordsToFind[i])
{
firewallLogString = firewallLogString + '\n';
condensedFirewallLog << firewallLogString;
cout << firewallLogString;
}
}
}
condensedFirewallLog.close();
firewallLog.close();
}
When I run the program it will compare the string, and if it matches it will only print out the specific word instead of the string. Any help would be much appreciated.
If I understand your problem correctly, you want to check if the line contains one of the word and print it if it does.
Right now what you are doing is this:
if(firewallLogString == wordsToFind[i])
Which checks if the string exactly matches the word. So, if the string contains one of the word but has other words in it, the test will fail.
Instead, check if the word is part of the string, like this:
if(firewallLogString.find(wordsToFind[i]) != string::npos)
There is something wrong in your code.
in this line
getline(firewallLog, firewallLogString);
you are reading a line, not a word, but then later you are comparing the whole line with a word from your array. Your IF shall not work actually.
Instead you need to use strstr method, to lookup for any word in your firewallLogString and if it finds you do the rest of your code.
Use std::string's find method to find the occurrence of your pattern words.