c++ Script that finds questions in string - c++

Question

I am new at coding , been coding for about a week and i am trying to do a script that finds the "?" and the "." in the script , then outputs their position in the script and i use those value to print the question to a text file.
Except it does not really work.
If you put the value in like this, it works.
myfile << test.substr( 18, 20 )
But like this it does not work it just print the whole script from the value of dot[0] until the end of the script.
myfile << test.substr( dot[0], interrogation[0] )
The way that i use to find the "?" position in the string is also not very accurate.
Where there is the .
if(x > 0){
I had a while loop but i replaced it for debugging reasons .
This is the whole code.
If you can help me i appreciate it.
Thanks.
#include <fstream>
#include <iostream>
#include <string>
#include <vector>
using namespace std;
int main (){
std::vector< int > interrogation ;
std::vector< int > dot;
string look = "?";
string look_again = ".";
string test = "ver. o que e isto? nao sei. ola? adeus. fghfghfhfghf";
string::size_type pos = test.find(look);
string::size_type sop = test.find(look_again);
string::size_type exc = test.find(look_again_again);
while (pos != std::string::npos)
{
int a = pos ;
int b = sop;
cout << " . found at : " << sop << std::endl;
cout << " ? found at : " << pos << std::endl;
interrogation.push_back(a);
dot.push_back(b);
string fragment = test.substr (0 , pos ); // works
//cout << fragment << endl ;
string fragment2 = test.substr (0 , sop ); // works
//cout << fragment2 << endl ;
pos = test.find(look, pos + 1);
sop = test.find(look_again, sop + 1);
}
int x = 1;
if(x > 0){
int a = 1;
int q = dot[a];
int w = interrogation[a];
// to save text
// to save text
string save = "saved_question.txt" ;
ofstream myfile;
myfile.open (save.c_str(), ios::app);
myfile << test.substr( 18, 20 ) + "\n" ;
myfile.close();
cout << "Question saved in text file" << endl;
}
}

Answer 1

The code is not finished yet but i got it working with help.
Thanks
#include <fstream>
#include <iostream>
#include <string>
#include <vector>
using namespace std;
int main (){
std::vector< int > interrogation ;
std::vector< int > dot;
//std::vector< int > exclamation;
string look = "?";
string look_again = ".";
string look_again_again = "!";
string test = " ver.o que e isto? nao sei. ola? adeus.";
string::size_type pos = test.find(look);
string::size_type sop = test.find(look_again);
while (pos != std::string::npos)
{
int a = pos ;
int b = sop;
cout << " . found at : " << sop << std::endl;
cout << " ? found at : " << pos << std::endl;
// cout << " ! found at : " << exc << std::endl;
interrogation.push_back(a);
dot.push_back(b);
//exclamation.push_back(c);
string fragment = test.substr (0 , pos ); // works
//cout << fragment << endl ;
string fragment2 = test.substr (0 , sop) ; // works
//cout << fragment2 << endl ;
string fragment3 = test.substr (dot.back() + 1, interrogation.back() - dot.back()); // works
cout << fragment3 << endl ;
pos = test.find(look, pos + 1);
sop = test.find(look_again, sop + 1);
}
}

Answer 2

You can do something like this:
void function(string str) {
string sentence = "";
for(int i=0; i < str.length(); i++) {
if(str[i] == '.' || str[i] == '!')
sentence = ""; // the sentence is not a question so clear the sentence
else if(str[i] == '?') {
sentence.push_back(str[i]);
cout << sentence << endl; // output the question - just replace cout with your ofstream
}
else
sentence.push_back(str[i]);
}
}
I think I've seen this question before though..