2-D Array or Matrix

// taking 2-D array as input
for(i = 0; i < 5; i++)
    {
        for(j = 0; j < 5; j++)
            {
                scanf("%d",&p);
                a[i][j] = p;
            }
    }
//same for output
for(i = 0; i < 5; i++)
    {
        for(j = 0; j < 5; j++)
            {
                p = a[i][j]
                printf("%d",p);
            }
    }

Take a matrix of 3x3 as input and print the sum of every column individually.

Pointers

which stores the address for a value.

      * = value at address

      & = address of

How to declare a pointer?

                              int * x;

                              char * y;

Function

Function

or you can say a reusable code

Find half max/min/max/min/max/min in a list of 100 values.

A function can return something or nothing.

•  a function which doesn't return anything is called a void function
•  a function which returns something is called a non-void function.

void function( ){

}

void function( int a ){

}

int function( ){

int a;

return a; }

int function(int a){

int b;

return b; }

int sumIt(int a, int b)
    {
        int c;
        c = a + b;
        return c;
    }
int main()
    {
        int ans;
        ans = sumIt(45,2);
        printf("%d",ans);
        return 0;
    }