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C++ Quiz #123

A Default Template Argument Fills the Gap

mediumTemplates

Triple has three type parameters, but the object is created with only two: Triple<int, std::string>. What is C for t, and what is printed?

📄 Code

1#include <iostream>
2#include <string>
3 
4template <typename A, typename B, typename C = A>
5class Triple {
6    A first;
7    B second;
8    C third;
9public:
10    Triple(A f, B s, C t) : first(f), second(s), third(t) {}
11    void print() const {
12        std::cout << first << " " << second << " " << third << "\n";
13    }
14};
15 
16int main() {
17    Triple<int, std::string> t(1, "one", 10);
18    t.print();
19    return 0;
20}