LAB 2: C BASICS ITS100: Computer and Programming Lab. Section 1 Instructor: Wirat Chinnan TAs: Ms. Sasirassamee Buavirat Mr. Thanasan Tanhermhong (Tum) Ms. Pattheera Panitsuk (Fon+) Mr. Pongsate Tangseng Mr. Chinorot Wangtragulsang Mr. Kanin Assantachai (Ob) 1

variable type 2 %c %d %ld %f %lf printf() and scanf()

printf() printf() is for output 3

scanf() scanf() is for input. Do not forget & in front of variable names. 4

Float and Integer di float d; int i;

Print Integer with getting input from keyboard 6 #include int main() { int n1; printf(“Enter a Number: “); scanf(“%d”,&n1); printf(“n1 = %d\n”, n1); return 0; } Enter a Number: 10 n1 = 10

Print Integer with getting input from keyboard 7 #include int main() { int n1,n2; printf(“Enter 1#: “); scanf(“%d”,&n1); printf(“Enter 2#: “); scanf(“%d”,&n2); printf(“output = %d %d\n”, n1,n2); return 0; } Enter 1#: 10 Enter 2#: 20 output = 10 20

Reads in two integer and prints out the result of the first number divided by the second number. 8 #include int main() { int n1,n2, ans; printf(“Enter two numbers: ”); scanf(“%d %d”,&n1,&n2); ans = n1/n2; // mathematic expression printf(“Remainder = %d\n”, ans); return 0; } Enter two Numbers: 21 6 Remainder = 3

Reads in two decimal and prints out the result of the first number divided by the second number. 9 #include int main() { float n1,n2, ans; printf(“Enter two numbers: ”); scanf(“%f %f”,&n1,&n2); ans = n1/n2; printf(“Remainder = %f\n”, ans); return 0; } Enter two Numbers: 21 6 Remainder =

Reads in two integer and prints out the remainder of the first number divided by the second number. 10 #include int main() { int n1,n2, ans; printf(“Enter two numbers: ”); scanf(“%d %d”,&n1,&n2); ans = n1%n2; // % means modulo operation printf(“Remainder = %d\n”, ans); return 0; } Enter two Numbers: 22 6 Remainder = 4

Mathematical Functions #include All of these functions require arguments in float and return float 11

Finds the square root of an input. 12 #include int main() { float n1, ans; printf(“Enter a number: ”); scanf(“%f”,&n1); ans = sqrt(n1); printf(“square root = %f\n”, ans); return 0; } Enter a number : 3 square root =

Finds the power of an input. 13 #include int main() { int n1,n2, ans; printf(“Enter two numbers: ”); scanf(“%d %d”,&n1,&n2); ans = pow(n1,n2); printf(“n1 power n2 = %d\n”, ans); return 0; } Enter two Numbers: 2 3 n1 power n2 = 8

To Do in Class Exercise Call your TA when you finished. You may take a break Be ready for the speed test at

Speed Test Speed test should be treated just like a real exam. Rules: No talking. Be quiet. No mobile phone. No electronic devices other than your PC No Internet No cheating Cheating will result in a severe penalty TAs will not help you (except when your PC crashes). Time allowed: 45 minutes. 15

Speed Test Instruction Write your name on the question sheet. Create all workspace on your ‘Desktop’ and set workspace’s name follow: Sx_ID_Gx Example : S1_ _G1 (for Section 1 ID Group 1) Example : S1_ _G2 (for Section 1 ID Group 2) When you finished Raise your hand to signal the assigned TA TA grades your work Quietly leave the room DO NOT bring the question sheet out. Leave it on your table. 16