//OPERATIONS ON A MATRIX

#include<stdio.h>

void mat_read(int [20][20],int,int);
void mat_add(int [20][20],int [20][20],int [20][20],int,int);
void mat_write(int [20][20],int,int);
void mat_product(int [20][20],int [20][20],int [20][20],int,int,int);
void mat_transpose(int [20][20],int,int);
void mat_triangles(int [20][20],int,int);
int i,j,k;
int mat1[20][20],mat2[20][20],mat3[20][20];
void main()
{
int r1,c1,r2,c2,r3,c3,opt;

clrscr();
					//MENU
do
  {
  printf("1.Add the Arrays\n2.Multiply the arrays\n");
  printf("3.Transpose of an array\n4.Lower triangular and Upper triangle\n");
  printf("5.Exit\n");
  printf("Enter the option\n");
  scanf("%d",&opt);
  switch(opt)
		 {
		 case 1:
		 {

					//READING MATRICES
		 printf("Enter the row and column of the Matrices\n");
		 scanf("%d%d",&r1,&c1);

		 clrscr();
		 printf("Enter the first Matrix");
		 mat_read(mat1,r1,c1);

		 clrscr();
		 printf("Enter the Second Matrix\n");
		 mat_read(mat2,r1,c1);

					//ADDING
		 mat_add(mat1,mat2,mat3,r1,c1);

					//SUM
		 clrscr();
		 printf("Sum Matrix\n");
		 mat_write(mat3,r1,c1);

		 getch();
		 clrscr();
		 break;
		 }

		 case 2:
		 {
					//READING MATRICES
		 printf("Enter the row and column of First Matrix\n");
		 scanf("%d%d",&r1,&c1);

		 printf("Enter the row and column of Second Matrix\n");
		 scanf("%d%d",&r2,&c2);

		 if(c1!=r2)

			printf("Multiplication not possible!\n");
		 else
			 {
			 clrscr();
			 printf("Enter the First Matrix\n");
			 mat_read(mat1,r1,c1);

			 clrscr();
			 printf("Enter the Second Matrix\n");
			 mat_read(mat2,r2,c2);


					//MULTIPLICATION

			 mat_product(mat1,mat2,mat3,r1,c1,c2);

			 clrscr();

			 printf("The Product Matrix is\n");
			 mat_write(mat3,r1,c2);

			 }
		 getch();
		 clrscr();
		 break;
		 }

		 case 3:
		 {
					//READING MATRIX
		 printf("Enter the number of rows and columns of the Matrix\n");
		 scanf("%d%d",&r1,&c1);

		 clrscr();
		 mat_read(mat1,r1,c1);

		 clrscr();
		 printf("Given Matrix\n");
		 mat_write(mat1,r1,c1);
		 printf("\n");

					  //TRANSPOSE
			 printf("Transpose is\n");
			 mat_transpose(mat1,r1,c1);

		 getch();
		 clrscr();
		 break;
		 }

		 case 4:
		 {
					//READING MATRIX
		 printf("Enter the number of rows and columns of the Matrix\n");
		 scanf("%d%d",&r1,&c1);

		 if(r1!=c1)
			printf("Square Matrix Required!");
		 else
			{
			clrscr();
			printf("Enter the Matrix\n");
					mat_read(mat1,r1,c1);
					//LOWER TRIANGLE
					//UPPER TRIANGLE
			mat_triangles(mat1,r1,c1);

			}

		 getch();
		 clrscr();
		 break;
		 }

		 case 5:
				 exit();

		 default:
				  printf("Invalid Entry!\n");
				  getch();
				  clrscr();

		 }


  }while(opt!=5);

getch();
}
void mat_read(int mat[20][20],int row,int col)
				{
				for(i=0;i<row;i++)
					{
					printf("Enter row %d\n",i+1);
					for(j=0;j<col;j++)
					scanf("%d",&mat[i][j]);
					}

				}
void mat_add(int mat1[20][20],int mat2[20][20],int mat3[20][20],int row,int col)
				 {
				 for(i=0;i<row;i++)
					 for(j=0;j<col;j++)
						mat3[i][j]=mat1[i][j]+mat2[i][j];

				 }

void mat_write(int mat[20][20],int row,int col)
				 {
				 for(i=0;i<row;i++)
					 {
					 printf("\n");
					 for(j=0;j<col;j++)
					 printf("\t%2d",mat[i][j]);
					 }
				 }
void mat_product(int mat1[20][20],int mat2[20][20],int mat3[20][20],int r1,int c1,int c2)
				 {
				 for(i=0;i<r1;i++)
					 for(j=0;j<c2;j++)
						 for(k=0;k<c1;k++)
							 mat3[i][j]+=mat1[i][k]*mat2[k][j];
				 }
void mat_transpose(int mat[20][20],int row,int col)
				 {
				 for(i=0;i<col;i++)
					 {
					 printf("\n");
					 for(j=0;j<row;j++)
						  printf("\t%2d",mat[j][i]);
					 }
				 }
void mat_triangles(int mat[20][20],int row,int col)
				 {
				 int sum=0;
				 printf("Lower Triangle is\n");
				 for(i=0;i<row;i++)
					 {
					 printf("\n");
					 for(j=0;j<=i;j++)
						 {
						 printf("\t%2d",mat[i][j]);
						 sum+=mat[i][j];
						 }
					 }
				 printf("\nSum of Lower Triangle is:%d",sum);

				 sum=0;
				 printf("\n");
				 printf("Upper Triangle is\n");
				 for(i=0;i<row;i++)
					{
					printf("\n");
					for(j=0;j<col-i;j++)
						{
						printf("\t%2d",mat[i][j]);
						sum+=mat[i][j];
						}
					}
				 printf("\nSum of Upper Triangle is:%d",sum);

				 }

/*SAMPLE OUTPUT

1.Add the Arrays
2.Multiply the arrays
3.Transpose of an array
4.Lower triangular and Upper triangle
5.Exit
Enter the option
1
Enter the row and column of the Matrices
2
3
Enter the first Matrix
Enter row 1
1
2
2
Enter row 2
2
3
4
Enter the Second Matrix
Enter row 1
7
4
9
Enter row 2
3
6
5
Sum Matrix
			8       6      11
			5       9       9
___________________________________

1.Add the Arrays
2.Multiply the arrays
3.Transpose of an array
4.Lower triangular and Upper triangle
5.Exit
Enter the option
2
Enter the row and column of First Matrix
2 2
Enter the row and column of Second Matrix
2 3
Enter the First Matrix
Enter row 1
2 5
Enter row 2
6 3
Enter the Second Matrix
Enter row 1
6 4 9
Enter row 2
5 2 8
The Product Matrix is

		  37      18      58
		  51      30      78
____________________________________

1.Add the Arrays
2.Multiply the arrays
3.Transpose of an array
4.Lower triangular and Upper triangle
5.Exit
Enter the option
3
Enter the number of rows and columns of the Matrix
2 3
Enter the Matrix
Enter row 1
3 5 7
Enter row 2
2 9 3
Given Matrix

			3       5       7
			2       9       3
Transpose is

			3       2
			5       9
			7       3
____________________________________

1.Add the Arrays
2.Multiply the arrays
3.Transpose of an array
4.Lower triangular and Upper triangle
5.Exit
Enter the option
4
Enter the number of rows and columns of the Matrix
3 3
Enter the Matrix
Enter row 1
2 5 7
Enter row 2
4 6 8
Enter row 3
1 6 3
Lower Triangle is

			2
			4       6
			1       6       3
Sum of Lower Triangle is:22
Upper Triangle is

			2       5       7
			4       6
			1
Sum of Upper Triangle is:25
____________________________________

*/