Given a matrix of order m*n then the task is to find the frequency of even and odd numbers in the matrix
Examples:
Input : m = 3, n = 3 { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } Output : Frequency of odd number = 5 Frequency of even number = 4 Input : m = 3, n = 3 { 10, 11, 12 }, { 13, 14, 15 }, { 16, 17, 18 } Output : Frequency of odd number = 4 Frequency of even number = 5
// C++ Program to Find the frequency // of even and odd numbers in a matrix #include <bits/stdc++.h> using namespace std;
#define MAX 100 // function for calculating frequency void freq( int ar[][MAX], int m, int n)
{ int even = 0, odd = 0;
for ( int i = 0; i < m; ++i) {
for ( int j = 0; j < n; ++j) {
// modulo by 2 to check
// even and odd
if ((ar[i][j] % 2) == 0)
++even;
else
++odd;
}
}
// print Frequency of numbers
cout << "Frequency of odd number = " << odd << endl;
cout << "Frequency of even number = " << even << endl;
} // Driver code int main()
{ int m = 3, n = 3;
int array[][MAX]
= { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } };
freq(array, m, n);
return 0;
} |
Frequency of odd number = 5 Frequency of even number = 4
Time Complexity: O(m*n), Where m is the number of rows and n is the number of columns in the given matrix.
Auxiliary Space: O(1)
Approach: Using Recursive method
// C++ Program to Find the frequency // of even and odd numbers in a matrix #include <bits/stdc++.h> using namespace std;
#define MAX 100 int even = 0, odd = 0;
void freq( int ar[][MAX], int m, int n, int i, int j) {
if (i == m) //base condition
{
cout << "Frequency of odd number = " << odd << endl;
cout << "Frequency of even number = " << even << endl;
return ;
}
if (j == n)
{
freq(ar, m, n, i+1, 0); //recursive call
return ;
}
if (ar[i][j] & 1)
++odd;
else
++even;
freq(ar, m, n, i, j+1); //recursive call
} int main() {
int m = 3, n = 3;
int array[][MAX] = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } };
freq(array, m, n, 0, 0);
return 0;
} |
Frequency of odd number = 5 Frequency of even number = 4
Time Complexity: O(m*n), Where m is the number of rows and n is the number of columns in the given matrix.
Auxiliary Space: O(m*n) , Each call to the function freq takes O(1) space in the call stack and the number of calls is m*n.
Please refer complete article on Frequencies of even and odd numbers in a matrix for more details!