# keeping track of numbers 1.0

Bjarne Stroustrup “Programming Principles and Practice Using C++”
Chapter 4 Drill 9
Using std_lib_facilities.h by Bjarne Stroustrup.

[code language=”cpp”]
// Philipp Siedler
// Bjarne Stroustrup’s PP
// Chapter 4 Drill 9

#include "std_lib_facilities.h"

int main()
{
cout << "Enter a double followed by m(meter) in(inch) ft(feet) or cm(centimeter or a ‘|’ to terminate the program:\n";
vector<double> numbers;
double x;
double y;
string unit;

while (cin >> x >> unit)
{
if (unit == "m")
{
y = x;
}

else if (unit == "in")
{
y = (x * 2.54)/100;
}

else if (unit == "ft")
{
y = ((x / 12)*2.54)/100;
}

else if (unit == "cm")
{
y = x/100;
}

else
{
cout << "I dont know what " << unit << " for a unit is, enter a valid unit \n";
continue;
}

cout << "you entered: " << x << " " << unit << "\n\n";

numbers.push_back(y);

double sum = 0;
for (int i = 0; i < numbers.size(); i++)
{
sum += numbers[i];
}
cout << "the sum of all numbers in m is: " << sum << " m\n";
sort(numbers);
cout << "the smallest so far is: " << numbers << " " << "m\n";
cout << "the largest so far is: " << numbers[numbers.size()-1] << " " << "m\n";
cout << "you have entered: " << numbers.size() << " values\n";
for (int i = 0; i < numbers.size(); i++)
{
cout << numbers[i] << ", ";
}
cout << "\n";
}
}
[/code]

```Output:
type in two doubles, followed by m(meter) in(inch) ft(feet) or cm(centimeter or a '|' to terminate the program:
5.4 m
you entered: 5.4 m

the sum of all numbers in m is: 5.4 m
the smallest so far is: 5.4 m
the largest so far is: 5.4 m
you have entered: 1 values
5.4,
4.3 ft
you entered: 4.3 ft

the sum of all numbers in m is: 5.4091 m
the smallest so far is: 0.00910167 m
the largest so far is: 5.4 m
you have entered: 2 values
0.00910167, 5.4,```