What is my code missing. no match for 'operator<<' in 'std::cout << vals'

Question

#include <iostream>
#include <iomanip>
#include <stdlib.h>

using namespace std;

struct twoVals
{
        int x;
    double y;
} number;

int main()
{
    number.x = 10;
    number.y = 20;

twoVals vals;
cout << vals << endl;

return 0;

}

Line 19: error: no match for 'operator<<' in 'std::cout << vals' compilation terminated due to -Wfatal-errors.

That is the error I get. How do I fix this? Is there anything else wrong with my code? Give examples.