1. CSCE 206 Lab Structured Programming in C
Fall 2018
Lecture 3
Ehsanul Haque Nirjhar

2. Today’s objective If-else logic block If-else if-else logic block
switch logic block

3. if-else

4. Sample Code-1 #include <stdio.h> int main(void) { int a;
printf("Enter a number:"); // Asks user for input
scanf("%d",&a);
if (a>0)
printf("%d is a positive number",a); }
else
printf("%d is not a positive number",a);
return 0;

5. if-else if-else

6. Sample Code-2
#include <stdio.h> int main(void) { int a; printf("Enter a number:"); // Asks user for input scanf("%d",&a); if (a>0) printf("%d is a positive number",a); } else if (a<0) printf("%d is a negative number",a); else printf("%d is zero",a); return 0;

7. Operators

8. Sample Code-3
#include <stdio.h> int main(void) { int a; printf("Enter a number:"); // Asks user for input scanf("%d",&a); if (a>0 || a==0) printf("%d is not a negative number",a); } else printf("%d is a negative number",a); return 0;

9. Nested if-else block

10. Sample Code-4
#include <stdio.h> int main(void) { int a; printf("Enter a number:"); // Asks user for input scanf("%d",&a); if (a>=0) if(a==0) printf("%d is zero",a); } else printf("%d is a positive number",a); printf("%d is a negative number",a); return 0;

11. switch case

12. Sample Code-5
#include <stdio.h> int main(void) { int a; printf("Enter a number:"); // Asks user for input scanf("%d",&a); switch(a){ case 0: printf("Zero"); break; } case 1: printf("One"); default: printf("No data"); return 0;

13. Now it’s your turn!

14. Practice Problem-1
Write a program that takes an integer as input and determines whether it is odd or even. It gives a proper sentence as output.
Tips: Use if-else block

15. Practice Problem-2
Write a program that takes 3 integers as input and prints out the largest number of them.
Tips: Use if-else if-else block

16. Practice Problem-3
Try problem 1 using switch case.