C++ Template compilation error

Question

I am new to templates and I am trying to test this out after reading up on how to do templates, but I'm getting a compilation error and my code looks the exact same as the example I took from. I create a function and I have a template, but when I compile it I get the following error:

15 20 C:\Users\Fire\Desktop\test.cpp [Error] call of overloaded 'max(int, int)' is ambiguous

15 20 C:\Users\Fire\Desktop\test.cpp [Note] candidates are:

7 3 C:\Users\Fire\Desktop\test.cpp [Note] T max(T, T) [with T = int]

The code is as follows:

#include <iostream>
using namespace std;

template<typename T>
T max(T a, T b){
    return (a > b)? a: b;
}    

int main(){
    cout << max<int>(10, 40);
    return 0;
}

Possible duplicate of [error: call of overloaded ‘max(int, int)’ is ambiguous](https://stackoverflow.com/questions/9097509/error-call-of-overloaded-maxint-int-is-ambiguous) — xskxzr, Feb 07 '18 at 14:36

score 4 · Answer 1 · answered Feb 07 '18 at 02:46

4

std::max is part of the std namespace. You are doing using namespace std and resolving all functions without the std qualifier. This means you have 2 versions of max in your code. Yours and namespace std. To solve this, never do using namespace std.

answered Feb 07 '18 at 02:46

Fantastic Mr Fox

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Thank you I had no idea! – Shinji-san Feb 07 '18 at 02:52
@Shinji-san If this answered your question please mark it as the correct answer. – Fantastic Mr Fox Dec 12 '18 at 23:57

score 1 · Accepted Answer · answered Feb 07 '18 at 02:43

1

std::max is a function defined in C++. Call your function myMax or something like that and it should work

answered Feb 07 '18 at 02:43

Mitch

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C++ Template compilation error

2 Answers2