# To perform following operations: -> Addition of two matrices, Transpose & Sum of upper and lower triangular

Program:

```#include<stdio.h>
void main()
{
int i,j,c,r,k;
int a[20][20],b[20][20],ma[20][20],choice;
printf("Enter an operation");
printf("\n1. Addition of matrices\n2. Transpose\n3. Upper triangular matrix\n4. Lower triangular matrix\n");
scanf("%d",&choice);
switch(choice)
{
case 1:
printf("\nEnter the value for row and column: ");
scanf("%d%d",&c,&r);
printf("\nEnter the value for matrix A\n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
scanf("%d",&a[i][j]);
}

}
printf("\nEnter the value for matrix B\n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
scanf("%d",&b[i][j]);
}

}
printf("\nMatrix A is\n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
printf("%d",*(*(a+i)+j));
}
printf("\n");
}
printf("\nMatrix B is:\n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
printf("\t%d",*(*(b+i)+j));
}

printf("\n");
}

for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
*(*(ma+i)+j)=*(*(a+i)+j)+*(*(b+i)+j);
}}
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
printf("\t%d",*(*(ma+i)+j));
}
printf("\n");
}
break;
case 2:
printf("\n\tEnter the value for row and column:  ");
scanf("%d%d",&c,&r);
printf("\n\tEnter the value for matrix \n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
scanf("%d",&a[i][j]);
}

}
printf("\n\t matrix is:\n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
printf("\t%d",*(*(a+i)+j));
}
printf("\n");
}
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{ *(*(b+i)+j)=*(*(a+j)+i);
}
}
printf("\n\t Transpose of the matrix is:\n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
printf("\t%d",*(*(b+i)+j));
}
printf("\n");
}
break;
case 3:
printf("\n\tEnter the value for row and column:  ");
scanf("%d%d",&c,&r);
printf("\n\tEnter the value for matrix \n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
scanf("%d",&a[i][j]);
}

}
printf("\n\t matrix is:\n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
printf("\t%d",*(*(a+i)+j));
}
printf("\n");
}
printf("Upper triangular matrix is:\n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{ if(i>=j)
*(*(a+i)+j)=0;
}
}
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
printf("%d  ",*(*(a+i)+j));
}
printf("\n");
}

break;
case 4:
printf("\n\tEnter the value for row and column:  ");
scanf("%d%d",&c,&r);
printf("\n\tEnter the value for matrix \n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
scanf("%d",&a[i][j]);
}

}
printf("\n\t matrix is:\n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
printf("\t%d",*(*(a+i)+j));
}
printf("\n");
}

printf("lower triangular matrix is:\n");
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{ if(i<=j)
*(*(a+i)+j)=0;
}
}
for(i=0;i<c;i++)
{
for(j=0;j<r;j++)
{
printf("%d  ",*(*(a+i)+j));
}
printf("\n");
}
break;
}
}```

OUTPUT: