C++ → Basics → Input → Arithmetic → Conditions → Loops → Array → Multidimensional Arrays

The multidimensional arrays in C++ Construction and Examples. The multidimensional arrays are arrays within an array.

For example, an array with two rows and three columns

1   2   3
4   5   6

can be written as

#include <iostream>
using namespace std;
int main()
{
int myarray[2][3] = {{1, 2, 3},{4, 5, 6}};
cout << myarray[0][0] << endl;
cout << myarray[0][2] << endl;
cout << myarray[1][2] << endl;
cout << myarray[1][1] << endl;
return 0;
}

Where int myarray[2][3] means array of size 2 rows and 3 columns. And,
myarray[0][0] means display element at row-1 and column-1.
myarray[0][2] means display element at row-1 and column-3.
myarray[1][2] means display element at row-2 and column-3.
myarray[1][1] means display element at row-2 and column-2.

All elements of the above multidimensional array (two rows and three columns) can be access using nested for loop. For example

#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
int myarray[2][3] = {{1, 2, 3},{4, 5, 6}};
for (int i=0; i<2; i++)
{
for (int j=0; j<3; j++)
{
cout << setw(4) << myarray[i][j];
}
cout << endl; //to change line after each row
}
}

Here we use setw(4) to include 4 spaces before each element to separate them. And to use setw() we have to include #include <iomanip> library.

Q.1 Write a program in C++ that takes marks in 4 subjects of 5 different students.

#include <iostream>
using namespace std;
int main()
{
string students[5] = {"A", "B", "C", "D", "E"};
string subjects[4] = {"Math", "Finance", "C++", "Matlab"};
int marks;
for (int i =0; i<5; i++)
{
for (int j=0; j<4; j++)
{
cout << "Enter Marks of Student " << students[i] << ": " << endl;
cout << "Subject " << subjects[j] << ": ";
cin >> marks;
}
}
return 0;
}

Q.2 Write a program in C++ that takes marks in 4 subjects of 5 different students and display total marks obtained by each student.

#include <iostream>
using namespace std;
int main()
{
string students[5] = {"A", "B", "C", "D", "E"};
string subjects[4] = {"Math", "Finance", "C++", "Matlab"};
int marks[4];
for (int i =0; i<5; i++)
{
int total_marks = 0;
for (int j=0; j<4; j++)
{
cout << "Enter Marks of Student " << students[i] << ": " << endl;
cout << "Subject " << subjects[j] << ": ";
cin >> marks[j];
total_marks = total_marks + marks[j];
}
cout << "Marks obtained by student " << students[i] << " are: " << total_marks << endl;
}
return 0;
}

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