编译C ++代码时出现编译错误

Question

I am trying to compile a C++ source file but I hit the below error when I try to compile it.

Error :

error: 'template class std::map' used without template parameters

I get the error in the line which has mp.find(someString) .

map<string, int *> mp;
sub = "xyz";
if(mp.find(sub) != map::end) {  
   doSomething();
}

I get the error when the if statement is executed.

How can I resolve this issue?

Answer 1

use mp.end() instead of map::end

update :

if(mp.find(sub) != map::end) { 

to

if(mp.find(sub) != mp.end()) {
//                 ^^^^^^^^

see std::map::end reference

Answer 2

You need to use mp.end :

 if(mp.find(sub) != mp.end() ) {

this reference for find shows a more extensive example.

Answer 3

You should update your code to :

if(mp.find(sub) != mp.end())
//                 ^^^^^^^^

The end() method returns an iterator referring to the past-the-end element in the map container.

http://www.cplusplus.com/reference/map/map/end/

Maybe you were trying to use std::end who is a C++11 feature :

if(mp.find(sub) != std::end(mp))
//                 ^^^^^^^^^^^^

In this case, std::end(mp) has exactly the same behaviour as mp.end() .

Take a look at the documentation : http://www.cplusplus.com/reference/iterator/end/