Please help - Array - out of range error

[JoshuaCarman]

Hi All,

Doing an assignment with one aspect being working out the maximum amount of a material used. Loading the material used into an array, then a maximum function that returns the highest. However, I get an out of range error. I thought I understood out of range issues with arrays..I only have 5 elements! Please help!

Output==================
0.61/1.7/0.52/1.34/0.25
The minimum isterminate called after throwing an instance of 'std::out_of_range'
what(): array::at: __n (which is 5) >= _Nm (which is 5)

#include <iostream>
#include <iomanip>
#include <array>
#include <string>

using namespace std;

float maximum(array<float, 5> score);

int main()
{    

    array<float, 5> MaterialusedArray {0.61, 1.70, 0.52, 1.34, 0.25};

    std::cout << MaterialusedArray.at(0)
              << "/" << MaterialusedArray.at(1)
              << "/" << MaterialusedArray.at(2)
              << "/" << MaterialusedArray.at(3)
              << "/" << MaterialusedArray.at(4)
              << std::endl;

    std::cout << "The maximum is" << maximum(MaterialusedArray);


    return 0;
}

float maximum(array<float, 5> score)
{
    float num = score.at(0);

    for (unsigned int i=1; 1<score.size(); i++)
    {
        if (score.at(i) > num)
            num = score.at(i);
    }
    return num;
}

[seeplus]

for (unsigned int i=1; 1<score.size(); i++)

you have 1 < rather than i < !

[Thomas1965]

Have a closer look at 1<score.size();
It will always be true.

[JoshuaCarman]

omg.... thank you so much... My brain is so burnt out.

The error is no longer there, but the output is showing the 1.70 element.. which isn't the lowest >_>_>_>_>

EDIT: WHoops im confused again, this is my maximum function, NOT my minimum function.

Thank you for the help!

[seeplus]

also note that you are passing the array by value, rather than by reference - so a copy of the array is performed when passing to maximum. Use const array<float, 5>& instead.

Also note, that there is an easier way to calculate the maximum value

#include <iostream>
#include <iomanip>
#include <array>
#include <string>
#include <algorithm>

using namespace std;

int main()
{
	array<float, 5> MaterialusedArray {0.61, 1.70, 0.52, 1.34, 0.25};

	std::cout << MaterialusedArray.at(0)
		<< "/" << MaterialusedArray.at(1)
		<< "/" << MaterialusedArray.at(2)
		<< "/" << MaterialusedArray.at(3)
		<< "/" << MaterialusedArray.at(4)
		<< std::endl;

	std::cout << "The maximum is " << *std::max_element(MaterialusedArray.begin(), MaterialusedArray.end());
}

[JoshuaCarman]

We are only 1st year uni - and we are only just getting into passing by reference.

Also, this assignment is supposed to be modular, and there is many values to pass through minimum, maximum, and average functions.. So your suggestion is a lil over my head and doesn't fit the brief, but thank you for the insight.

[againtry]

Now, you have both:

#include <iostream>
#include <iomanip>
#include <array>
#include <string>

using namespace std;

float minimum(array<float, 5> score); // <--

int main()
{

    array<float, 5> MaterialusedArray {0.61, 1.70, 0.52, 1.34, 0.25};

    std::cout << MaterialusedArray.at(0)
              << "/" << MaterialusedArray.at(1)
              << "/" << MaterialusedArray.at(2)
              << "/" << MaterialusedArray.at(3)
              << "/" << MaterialusedArray.at(4)
              << std::endl;

    std::cout << "The maximum is" << minimum(MaterialusedArray); // <--


    return 0;
}

float minimum(array<float, 5> score) // <--
{
    float num = score.at(0);

    for (unsigned int i=1; i<score.size(); i++)
    {
        if (score.at(i) < num) // <--
            num = score.at(i);
    }
    return num;
}