🖥️ CS111 — Introduction to Programming Lab
- The Programming Lab (CS111) provides hands-on experience in coding, helping students implement algorithms, develop programs, and strengthen computational thinking through practical exercises.
Basic C programming exercises for beginners
Click any program below to view the complete source code
🎯 Basic Operations
1. add.c · Addition of Two Numbers
c
#include <stdio.h>
int main(void) {
int a = 2, b = 3;
printf("%d + %d = %d\n", a, b, a + b);
return 0;
}32. sum.c · Sum of Two Numbers
c
#include <stdio.h>
int main(void) {
int a = 1, b = 2;
printf("Sum: %d\n", a + b);
return 0;
}24. mul.c · Multiplication
c
#include <stdio.h>
int main(void) {
int a = 6, b = 7;
printf("%d * %d = %d\n", a, b, a * b);
return 0;
}17. division.c · Division Operation
c
#include <stdio.h>
int main(void) {
double a = 10.0, b = 3.0;
printf("%.2f / %.2f = %.2f\n", a, b, a / b);
return 0;
}14. dif1.c · Difference Method 1
c
#include <stdio.h>
int main(void) {
int a = 10, b = 3;
int diff = a - b;
printf("Difference: %d\n", diff);
return 0;
}15. dif2.c · Difference Method 2 (Absolute)
c
#include <stdio.h>
#include <stdlib.h>
int main(void) {
int a = 5, b = 12;
int diff = abs(a - b);
printf("Absolute difference: %d\n", diff);
return 0;
}20. hello.c · Hello World
c
#include <stdio.h>
int main(void) {
printf("Hello, world!\n");
return 0;
}📐 Geometric Calculations
2. areac.c · Area of Circle
c
#include <stdio.h>
int main(void) {
double r = 1.5;
printf("Area of circle (r=%.2f): %.4f\n", r, 3.14159 * r * r);
return 0;
}3. areaR.c · Area of Rectangle
c
#include <stdio.h>
int main(void) {
double length = 5.0, width = 3.0;
double area = length * width;
printf("Area of rectangle: %.2f\n", area);
return 0;
}4. areaRec.c · Area of Rectangle (User Input)
c
#include <stdio.h>
int main(void) {
double length, width;
printf("Enter length: ");
scanf("%lf", &length);
printf("Enter width: ");
scanf("%lf", &width);
printf("Area: %.2f\n", length * width);
return 0;
}23. milage.c · Compute Mileage
c
#include <stdio.h>
int main(void) {
double distance = 150.0, fuel = 10.0;
printf("Mileage: %.2f km/l\n", distance / fuel);
return 0;
}🧮 Calculators
6. Calc.c · Simple Calculator
c
#include <stdio.h>
int main(void) {
double a, b;
char op;
printf("Enter operation (a op b): ");
scanf("%lf %c %lf", &a, &op, &b);
switch(op) {
case '+': printf("%.2f\n", a + b); break;
case '-': printf("%.2f\n", a - b); break;
case '*': printf("%.2f\n", a * b); break;
case '/': printf("%.2f\n", a / b); break;
default: printf("Invalid operator\n");
}
return 0;
}7. Calculator.c · Enhanced Calculator
c
#include <stdio.h>
int main(void) {
double num1, num2, result;
char operator;
printf("Enter first number: ");
scanf("%lf", &num1);
printf("Enter operator (+, -, *, /): ");
scanf(" %c", &operator);
printf("Enter second number: ");
scanf("%lf", &num2);
switch(operator) {
case '+':
result = num1 + num2;
printf("%.2f + %.2f = %.2f\n", num1, num2, result);
break;
case '-':
result = num1 - num2;
printf("%.2f - %.2f = %.2f\n", num1, num2, result);
break;
case '*':
result = num1 * num2;
printf("%.2f * %.2f = %.2f\n", num1, num2, result);
break;
case '/':
if(num2 != 0) {
result = num1 / num2;
printf("%.2f / %.2f = %.2f\n", num1, num2, result);
} else {
printf("Error: Division by zero\n");
}
break;
default:
printf("Invalid operator\n");
}
return 0;
}🔢 Number Operations
16. DigitSum.c · Sum of Digits
c
#include <stdio.h>
int main(void) {
int n = 12345, sum = 0;
while(n) {
sum += n % 10;
n /= 10;
}
printf("Digit sum: %d\n", sum);
return 0;
}12. DecToBin.c · Decimal to Binary Conversion
c
#include <stdio.h>
void dec_to_bin(unsigned n) {
if(n > 1) dec_to_bin(n / 2);
printf("%u", n % 2);
}
int main(void) {
unsigned n = 13;
printf("%u in binary: ", n);
dec_to_bin(n);
printf("\n");
return 0;
}5. bitOE.c · Check Odd or Even (Bitwise)
c
#include <stdio.h>
int main(void) {
int n = 7;
if(n & 1)
printf("%d is odd\n", n);
else
printf("%d is even\n", n);
return 0;
}26. Powof2.c · Check Power of Two
c
#include <stdio.h>
int main(void) {
int n = 16;
int ok = (n > 0) && ((n & (n - 1)) == 0);
printf("%d is %spower of two\n", n, ok ? "" : "not ");
return 0;
}18. FibboSeries.c · Fibonacci Series
c
#include <stdio.h>
int main(void) {
int n = 10, a = 0, b = 1, next;
printf("Fibonacci Series: %d %d ", a, b);
for(int i = 2; i < n; i++) {
next = a + b;
printf("%d ", next);
a = b;
b = next;
}
printf("\n");
return 0;
}27. Prime.c · Check Prime Number
c
#include <stdio.h>
#include <math.h>
int main(void) {
int n = 17, ok = 1;
if(n <= 1) ok = 0;
else {
for(int i = 2; i <= sqrt(n); i++)
if(n % i == 0) {
ok = 0;
break;
}
}
printf("%d is %sprime\n", n, ok ? "" : "not ");
return 0;
}11. Dcprime.c · Check Prime (Optimized)
c
#include <stdio.h>
int main(void) {
int n = 29, isPrime = 1;
if(n <= 1) isPrime = 0;
else if(n == 2) isPrime = 1;
else if(n % 2 == 0) isPrime = 0;
else {
for(int i = 3; i * i <= n; i += 2) {
if(n % i == 0) {
isPrime = 0;
break;
}
}
}
printf("%d is %sprime\n", n, isPrime ? "" : "not ");
return 0;
}28. Primenum.c · Print Prime Numbers
c
#include <stdio.h>
#include <math.h>
int main(void) {
int limit = 20;
printf("Prime numbers up to %d: ", limit);
for(int n = 2; n <= limit; n++) {
int ok = 1;
for(int i = 2; i <= sqrt(n); i++)
if(n % i == 0) {
ok = 0;
break;
}
if(ok) printf("%d ", n);
}
printf("\n");
return 0;
}📝 String Operations
29. Reverse.c · Reverse a String
c
#include <stdio.h>
#include <string.h>
int main(void) {
char s[] = "hello";
printf("Original: %s\n", s);
printf("Reversed: ");
for(int i = strlen(s) - 1; i >= 0; i--)
putchar(s[i]);
putchar('\n');
return 0;
}8. caseconvert.c · Convert to Uppercase
c
#include <stdio.h>
#include <ctype.h>
int main(void) {
char s[] = "Hello World";
for(int i = 0; s[i]; i++)
s[i] = toupper((unsigned char)s[i]);
printf("%s\n", s);
return 0;
}9. caseconvert1.c · Convert to Lowercase
c
#include <stdio.h>
#include <ctype.h>
int main(void) {
char s[] = "HELLO WORLD";
for(int i = 0; s[i]; i++)
s[i] = tolower((unsigned char)s[i]);
printf("%s\n", s);
return 0;
}10. caseconvert2.c · Toggle Case
c
#include <stdio.h>
#include <ctype.h>
int main(void) {
char s[] = "HeLLo WoRLd";
for(int i = 0; s[i]; i++) {
if(isupper(s[i]))
s[i] = tolower(s[i]);
else if(islower(s[i]))
s[i] = toupper(s[i]);
}
printf("%s\n", s);
return 0;
}31. StrLen.c · String Length
c
#include <stdio.h>
int main(void) {
char str[] = "Hello World";
int len = 0;
while(str[len] != '\0')
len++;
printf("Length of '%s': %d\n", str, len);
return 0;
}25. Palindrome.c · Check Palindrome
c
#include <stdio.h>
#include <string.h>
int main(void) {
char str[] = "madam";
int len = strlen(str);
int isPalindrome = 1;
for(int i = 0; i < len / 2; i++) {
if(str[i] != str[len - 1 - i]) {
isPalindrome = 0;
break;
}
}
printf("%s is %sa palindrome\n", str, isPalindrome ? "" : "not ");
return 0;
}🔄 Comparison & Swap
21. Largest2.c · Largest of Two Numbers
c
#include <stdio.h>
int main(void) {
int a = 10, b = 20;
int largest = (a > b) ? a : b;
printf("Largest: %d\n", largest);
return 0;
}22. Largest3.c · Largest of Three Numbers
c
#include <stdio.h>
int main(void) {
int a = 10, b = 25, c = 15;
int largest = a;
if(b > largest) largest = b;
if(c > largest) largest = c;
printf("Largest: %d\n", largest);
return 0;
}33. swap1.c · Swap Using Temp Variable
c
#include <stdio.h>
int main(void) {
int a = 5, b = 10, temp;
printf("Before swap: a = %d, b = %d\n", a, b);
temp = a;
a = b;
b = temp;
printf("After swap: a = %d, b = %d\n", a, b);
return 0;
}34. Swap2.c · Swap Without Temp Variable
c
#include <stdio.h>
int main(void) {
int a = 5, b = 10;
printf("Before swap: a = %d, b = %d\n", a, b);
a = a + b;
b = a - b;
a = a - b;
printf("After swap: a = %d, b = %d\n", a, b);
return 0;
}🍬 Practice Problems
36. SweetDistribute.c · Distribute Sweets
c
#include <stdio.h>
int main(void) {
int sweets = 10, kids = 3;
printf("Each gets %d sweets\n", sweets / kids);
return 0;
}35. sweet.c · Sweet Distribution (Detailed)
c
#include <stdio.h>
int main(void) {
int sweets = 20, kids = 4;
printf("Total sweets: %d\n", sweets);
printf("Number of kids: %d\n", kids);
printf("Each kid gets: %d sweets\n", sweets / kids);
printf("Remaining: %d sweets\n", sweets % kids);
return 0;
}37. sweets.c · Sweets Calculation
c
#include <stdio.h>
int main(void) {
int total = 15, eaten = 3, remaining;
remaining = total - eaten;
printf("Total sweets: %d\n", total);
printf("Eaten: %d\n", eaten);
printf("Remaining: %d\n", remaining);
return 0;
}🔧 Miscellaneous
19. header_files.c · Header Files Example
c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
int main(void) {
printf("Header files example\n");
printf("Using stdio.h for input/output\n");
printf("Using stdlib.h for utilities\n");
printf("Using string.h for string operations\n");
printf("Using math.h for mathematical functions\n");
return 0;
}13. des.c · Descriptive Example
c
#include <stdio.h>
int main(void) {
printf("This is a descriptive program example\n");
printf("It demonstrates basic C syntax\n");
return 0;
}30. s.c · Simple Program
c
#include <stdio.h>
int main(void) {
printf("Simple test program\n");
return 0;
}38. test.c · Test Program
c
#include <stdio.h>
int main(void) {
printf("This is a test program\n");
printf("Testing basic C operations\n");
return 0;
}39. wsemi.c · Semicolon Example
c
#include <stdio.h>
int main(void) {
int x = 5;
int y = 10;
int sum = x + y;
printf("Sum of %d and %d is %d\n", x, y, sum);
return 0;
}