In c++ cin array is not performed in one cin statement. In this article we will learn about array input in c++. To understand array input, we first need to understand what an array is and how does it work.
Understanding Arrays
Arrays are used to store multiple values, rather than storing similar data in separate variables, which is tedious as well as memory consuming, we create an array, which is a container that contains multiple values. Written below is a code that is the record of 5 students marks in separate variables and then in an array.
#include <iostream>
using namespace std;
int main()
{
int student1 = 1;
int student2 = 2;
int student3 = 3;
int student4 = 4;
int student5 = 5;
cout << "marks of student1: " << student1 << endl;
cout << "marks of student2: " << student2 << endl;
cout << "marks of student3: " << student3 << endl;
cout << "marks of student4: " << student4 << endl;
cout << "marks of student5: " << student5 << endl;
}
Output of this code is :
marks of student1: 1
marks of student2: 2
marks of student3: 3
marks of student4: 4
marks of student5: 5
Now, the code written below is the same but data is stored in an array
#include <iostream>
using namespace std;
int main()
{
int student[5] = {1, 2, 3, 4, 5};
cout << "the marks of student 1 are : " << student[0] << endl;
cout << "the marks of student 2 are : " << student[1] << endl;
cout << "the marks of student 3 are : " << student[2] << endl;
cout << "the marks of student 4 are : " << student[3] << endl;
cout << "the marks of student 5 are : " << student[4] << endl;
}
The output of the following code is :
the marks of student 1 are : 1
the marks of student 2 are : 2
the marks of student 3 are : 3
the marks of student 4 are : 4
the marks of student 5 are : 5
Cin Array
If you want input from the user you need to cin array, but cin cannot be directly used in this case, it will show an error like the one given below
#include <iostream>
using namespace std;
int main()
{
int student[5] = {1, 2, 3, 4, 5};
cin >> student;
}
Output:
cinarray.cpp:6:12: error: invalid conversion from ‘int*’ to ‘long int’ [-fpermissive]
6 | cin >> student;
| ^~~~~~~
| |
| int*
cinarray.cpp:6:12: error: cannot bind rvalue ‘(long int)((int*)(& student))’ to ‘long int&’
So we use a for loop for the input of the array, the loop will run till the size of the array, and take input of array at every index, this is how cin array is executed in C++.
The code for cin array is written below :
#include <iostream>
using namespace std;
int main()
{
int student[5] = {1, 2, 3, 4, 5};
//cin array
for (int i = 0; i < 5; i++)
{
cout << "enter student marks " << endl;
cin >> student[i];
}
//output
cout << "the marks of student 1 are : " << student[0] << endl;
cout << "the marks of student 2 are : " << student[1] << endl;
cout << "the marks of student 3 are : " << student[2] << endl;
cout << "the marks of student 4 are : " << student[3] << endl;
cout << "the marks of student 5 are : " << student[4] << endl;
}
The output of code of cin array is :
enter student marks
1
enter student marks
2
enter student marks
3
enter student marks
4
enter student marks
5
the marks of student 1 are : 1
the marks of student 2 are : 2
the marks of student 3 are : 3
the marks of student 4 are : 4
the marks of student 5 are : 5
Conclusion
In this article we studied what are arrays, how do we store elements in arrays and how cin arrays take place. It is executed in a loop unlike other variables.