Algorithm::find on string

Hi, I am trying to use the 'find' function from the STL algorithms library on 'string' by using iterators only
(I am aware that string::find exists)

I am having trouble getting this to compile...any clues?

(This example should read the string and insert a '+' character before every '-' in the string "curr"

Code:

---

                String curr = "aaa-bbb-ccc";
                string::iterator plus = curr.begin();
                while(plus != curr.end())
                {
                        plus = find(plus,curr.end(),'-');
                        if(plus != curr.end())
                        {
                                curr.insert(plus,'+');
                                ++plus;
                        }
                }

---

any ideas?

Code:

---

q.cpp:19: error: no matching function for call to ‘find(__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >&, __gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, char)’

---

http://www.cplusplus.com/reference/algorithm/find/

Perhaps you need to include <algorithm>.

You seem to be using the insert method incorrectly, though. It can invalidate the iterator, so you need to use the return value.

Not sure why you got that compiler error, this is what I got:

Code:

---

stuff$ g++ strIter.cpp
strIter.cpp: In function ‘int main()’:
strIter.cpp:8: error: ‘String’ was not declared in this scope
strIter.cpp:8: error: expected ‘;’ before ‘curr’
strIter.cpp:9: error: ‘curr’ was not declared in this scope

---

Here's the complete program I put your code into:

Code:

---

1 #include <algorithm>
 2 #include <iostream>
 3 #include <string>
 4 using namespace std;
 5
 6 int main()
 7 {
 8    String curr = "aaa-bbb-ccc";
 9    string::iterator plus = curr.begin();
10    while(plus != curr.end())
11    {
12        plus = find(plus,curr.end(),'-');
13        if(plus != curr.end())
14        {
15            curr.insert(plus,'+');
16            ++plus;
17        }
18    }
19 }

---

Getting it to compile is a simple matter of changing "String" to "string" on line 8. However, as anon said, using insert invalidates your "plus" iterator. Indeed, when I run the program I get a segmentation fault.