Answer to Question #223677 in C for Jim

Question

1. Write a C program to find the frequency of even numbers in matrix using functions & dynamic memory allocation.

 

2. Write a C program to find the trace of (sum of diagonal element) matrix using

functions & dynamic memory allocation.

Answer 1

//Question 1
#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
//Implement function Input Matrix 
void InpMat(int** mat, int rows, int cols)//
{
	printf("Please enter elements matrix:\n");
	for (int i = 0; i < rows; i++)
	{
		for (int j = 0; j < cols; j++)
			scanf("%i", &mat[i][j]);
	}
}
//Implement function Out matrix
void OutMat(int** mat, int rows, int cols)//
{
	printf("===============================================================\n");
	for (int i = 0; i < rows; i++)
	{
		for (int j = 0; j < cols; j++)
			printf("%3d", mat[i][j]);
		printf("\n");
	}
}
//Function CntEven which return frequency even numbers
int CntEven(int** mat, int rows, int cols)
{
	int ans = 0;//count even numbers
	for (int i = 0; i < rows; i++)
	{
		for (int j = 0; j < cols; j++)
			if (mat[i][j] % 2 == 0)
				ans++;
	}
	return ans;
}
int main()
{
	//Alloc dynamic memory
	int rows, cols;
	printf("Please enter rows and columns of matrix:\n");
	scanf("%i%i", &rows, &cols);
	int** mat = (int**)malloc(sizeof(int*) * (size_t)rows);//size_t=unsigned int
	for (int i = 0; i < rows; i++)
		mat[i] = (int*)malloc(sizeof(int) * (size_t)cols);
	InpMat(mat, rows, cols);
	int frEven = CntEven(mat, rows, cols);
	printf("Frequency of even numbers: %i", frEven);
	free(mat);
	return 0;
}
//Question 2
#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
//Implement function Input Matrix 
void InpMat(int** mat, int n)//n-size of matrix
{
	printf("Please enter elements matrix:\n");
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < n; j++)
			scanf("%i", &mat[i][j]);
	}
}
//Function findTrace
long long findTrace(int** mat, int n)
{
	long long sum = 0;
	for (int i = 0; i < n; i++)
		sum += (int)mat[i][i];
	return sum;
}
int main()
{
	//Alloc dynamic memory
	int n;
	printf("Please enter size:\n");
	scanf("%i", &n);
	int** mat = (int**)malloc(sizeof(int*) * (size_t)n);//size_t=unsigned int
	for (int i = 0; i < n; i++)
		mat[i] = (int*)malloc(sizeof(int) * (size_t)n);
	InpMat(mat,n);
	long long sum = findTrace(mat, n);
	printf("Trace: %lld\n", sum);
	free(mat);
	return 0;
}