This document summarizes an lecture on applications of strings and pointers in C programming. It includes examples of using arrays of strings, pointer arithmetic, double pointers, scanf vs gets functions, generating Fibonacci series using recursion, and using the ceil() and floor() math functions. The lecture covers basic and advanced concepts of strings and pointers through examples and explanations.

1. Lecture
ON
Applications of Strings & Pointers
V.Radhesyam
Assistant professor
Department of IT:VRSEC

2. Radhesyam.V
Array of Strings
1. #include <stdio.h>
2. int main()
3. {
4. char charr[7][10] = {"sun","mon","tue","wed","thu","fri","sat"};
5. int i;
6. for(i=0;i<7;i++)
7. printf("%sn",charr[i]);
8. return 0;
9. }
2
Output:
sun
mon
tue
wed
thu
fri
sat

3. Radhesyam.V
Array of Strings
1. #include <stdio.h>
2. Void main()
3. {
4. char charr[7][10];
5. int i;
6. printf("enter string");
7. for(i=0;i<7;i++)
8. scanf("%s",charr[i]);
9. printf("string is ");
10. for(i=0;i<7;i++)
11. printf("%sn",charr[i]);
12. }
3
Maximum no of strings
Maximum string length

4. Radhesyam.V
Pointer arithmetic
4
1. void main()
2. {
3. int first, second, *p, *q, sum,sub,mul,di;
4. printf("Enter two integers n");
5. scanf("%d%d", &first, &second);
6. p = &first;
7. q = &second;
8. sum = *p + *q;
9. sub = *p - *q;
10.mul = (*p) * (*q);
11.di = (*p) /(*q);
12.printf("Sum of the numbers = %dn", sum);
13.printf("Sub of the numbers = %dn", sub);
14.printf("mul of the numbers = %dn", mul);
15.printf("div of the numbers = %dn", di);
16.}

5. Radhesyam.V
Double Pointer
5

6. Radhesyam.V
Double pointer Program
6
1. Void main()
2. {
3. int var = 120;
4. int *varptr = &var;
5. int **doubleptr = &varptr;
6. printf("Value of var = %dn", var );
7. printf("Value of var pointer = %dn", *varptr );
8. printf("Value of double pointer = %dn", **doubleptr);
9. printf("Address of var = %pn", &var );
10. printf("Address of var pointer = %pn", &varptr );
11. printf("Value in var pointer = %pn", varptr );
12. printf("Address of double pointer = %pn", *doubleptr);
13. printf("Value in double pointer = %pn", doubleptr);
14. }
Output:
Value of var = 120
Value of var pointer = 120
Value of double pointer = 120
Address of var = 0x7ffe25192bfc
Address of var pointer = 0x7ffe25192c00
Value in var pointer = 0x7ffe25192bfc
Address of double pointer = 0x7ffe25192bfc
Value in double pointer = 0x7ffe25192c00

7. Radhesyam.V
Scanf vs gets
7
Scanf() Gets()
scanf() function can read different
data types.
get() function will only get character
string data.
scanf() function takes the format
string and list of addresses of
variables. e.g. scanf(“%d”,
&number);
get() function takes the name of the
variable to store the received value.
e.g. gets(name);
Read multiple values One string
Scanf () reads input until it
encounters whitespace, newline or
End Of File (EOF)
gets () reads input until it encounters
newline or End Of File (EOF)

8. Radhesyam.V
Fibonacci Series Using Recursion
1. int fib(int n)
2. {
3. if (n <= 1)
4. return n;
5. return fib(n-1) + fib(n-2);
6. }
7. int main ()
8. {
9. int n = 9;
10. printf("%d", fib(n));
11. getchar();
12. return 0;
13. }
8

9. Radhesyam.V
Ceil()
#include <stdio.h>
#include <math.h>
int main()
{
double num = 8.33;
int result;
result = ceil(num);
printf("Ceiling integer of %.2f = %d", num, result);
return 0;
}
9
Output:
Ceiling integer of 8.33 = 9

10. Radhesyam.V
Floor()
#include <stdio.h>
#include <math.h>
int main()
{ double num = -8.33;
int result;
result = floor(num);
printf("Floor integer of %.2f = %d", num, result);
return 0;
}
10
Output:
Floor integer of -8.33 = -9