16. Program to Check Prime Number
#include <stdio.h>
#include<conio.h>
int main() {
int num = 7, i, flag = 0;
for (i = 2; i <= num / 2; i++) {
if (num % i == 0) {
flag = 1;
break;
}
}
if (flag == 0)
printf("Prime number");
else
printf("Not a prime number");
return 0;
getch();
}
Output
Prime number
17. Program to Print Prime Numbers from 1 to 10
#include <stdio.h>
#include<conio.h>
int main() {
int i, j, flag;
for (i = 2; i <= 10; i++) {
flag = 0;
for (j = 2; j <= i / 2; j++) {
if (i % j == 0) {
flag = 1;
break;
}
}
if (flag == 0)
printf("%d ", i);
}
return 0;
getch();
}
Output
2 3 5 7
18. Program to Find Fibonacci Series
#include <stdio.h>
#include<conio.h>
int main() {
int n = 5, a = 0, b = 1, c, i;
printf("%d %d ", a, b);
for (i = 2; i < n; i++) {
c = a + b;
printf("%d ", c);
a = b;
b = c;
}
return 0;
getch();
}
Output
0 1 1 2 3
19. Program Using Function (Addition)
#include <stdio.h>
#include<conio.h>
int add(int a, int b) {
return a + b;
}
int main() {
int result;
result = add(10, 20);
printf("Sum = %d", result);
return 0;
getch();
}
Output
Sum = 30
20. Program to Find String Length (Without strlen)
#include <stdio.h>
#include<conio.h>
int main() {
char str[] = "Hello";
int i = 0;
while (str[i] != '\0') {
i++;
}
printf("Length = %d", i);
return 0;
getch();
}
Output
Length = 5
21. Program to Reverse a String
#include <stdio.h>
#include<conio.h>
int main() {
char str[] = "Cprogram";
int i, len = 0;
while (str[len] != '\0') {
len++;
}
for (i = len - 1; i >= 0; i--) {
printf("%c", str[i]);
}
return 0;
getch();
}
Output
margorpC
22. Program to Copy One String to Another
#include <stdio.h>
#include<conio.h>
int main() {
char str1[] = "Hello";
char str2[10];
int i = 0;
while (str1[i] != '\0') {
str2[i] = str1[i];
i++;
}
str2[i] = '\0';
printf("Copied string: %s", str2);
return 0;
getch();
}
Output
Copied string: Hello
23. Program Using Pointer
#include <stdio.h>
#include<conio.h>
int main() {
int a = 10;
int *p;
p = &a;
printf("Value of a = %d\n", a);
printf("Value using pointer = %d", *p);
return 0;
getch();
}
Output
Value of a = 10
Value using pointer = 10
24. Program to Swap Two Numbers (Using Function)
#include <stdio.h>
#include<conio.h>
void swap(int *x, int *y) {
int temp;
temp = *x;
*x = *y;
*y = temp;
}
int main() {
int a = 5, b = 10;
swap(&a, &b);
printf("a = %d, b = %d", a, b);
return 0;
getch();
}
Output
a = 10, b = 5