CPP infinit while-loop error when reading in struct data? - c++

Question

I would like to use an infinite loop to read in Person struct (name, age, salary). I would like to break the loop when the user enters name as 'x'.
#include <iostream>
#include <vector>
using namespace std;
struct Person
{
char name[50];
int age;
float salary;
};
int main(int argc, const char * argv[]) {
Person p1;
vector <Person> p1_vec;
while (true) {
cout << "Enter Full name or simply 'x' to exit: ";
cin.get(p1.name, 50);
bool next_entry = strcmp(p1.name,"x");
if (!next_entry) {
break;
}
cout << "Enter age: ";
cin >> p1.age;
cout << "Enter salary: ";
cin >> p1.salary;
p1_vec.push_back(p1);
}
}

Answer 1

You need to ignore the new line character that you get after reading a salary input:
cin >> p1.salary;
doing:
cin >> p1.salary;
cin.ignore(1, '\n');
will make the code to stop here:
cin.get(p1.name, 50);
and wait for another user input!

Answer 2

cin state needs to be cleared after reading, try something like:
cin.clear();
cin.ignore(std::numeric_limits<streamsize>::max(), '\n');
For example (depending on the amount of error tolerance you want)
while (true)
{
cout << "Enter Full name or simply 'x' to exit: ";
cin.get(p1.name, 50);
cin.clear();
auto equal = strcmp(p1.name, "x")==0;
if (equal)
{
break;
}
cout << "Enter age: ";
cin >> p1.age;
cin.clear();
cout << "Enter salary: ";
cin >> p1.salary;
p1_vec.push_back(p1);
cin.clear();
cin.ignore(std::numeric_limits<streamsize>::max(), '\n');
}

Answer 3

cin.get(p1.name, 50) does not consume the \n, that remains in the input buffer after having entered a salary; so it skips the input and leaves the values blank.
Write cin >> p1.name and it should work properly.

Answer 4

After getting data from input buffer, you should clear it.
int main(int argc, const char * argv[]) {
Person p1;
vector <Person> p1_vec;
while (true) {
cout << "Enter Full name or simply 'x' to exit: ";
cin.get(p1.name, 50);
bool next_entry = strcmp(p1.name,"x");
if (!next_entry) {
break;
}
cout << "Enter age: ";
cin >> p1.age;
cout << "Enter salary: ";
cin >> p1.salary;
p1_vec.push_back(p1);
cin.clear();
cin.ignore();
}
}