## Algorithm

1. Input lower and upper bounds of the interval.
2. For each number i in the interval from lower to upper:
a. Check if i is a prime number.
i. If i is less than or equal to 1, skip to the next iteration.
ii. For j from 2 to the square root of i:
- If i is divisible by j, i is not a prime number. Skip to the next iteration.
iii. Display i as a prime number.
3. End.

## Code Examples

### #1 Code Example-C Programing Display Prime Numbers Between Two Intervals

Code - C Programming

#include <stdio.h>

int main() {
int low, high, i, flag;
printf("Enter two numbers(intervals): ");
scanf("%d %d", &low, &high);
printf("Prime numbers between %d and %d are: ", low, high);

// iteration until low is not equal to high
while (low < high) {
flag = 0;

// ignore numbers less than 2
if (low <= 1) {
++low;
continue;
}

// if low is a non-prime number, flag will be 1
for (i = 2; i <= low / 2; ++i) {

if (low % i == 0) {
flag = 1;
break;
}
}

if (flag == 0)
printf("%d ", low);

// to check prime for the next number
// increase low by 1
++low;
}

return 0;
}
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Output

cmd
Enter two numbers(intervals): 20
50
Prime numbers between 20 and 50 are: 23 29 31 37 41 43 47

### #2 Example-Display Prime Numbers when Larger Number is Entered first

Code - C Programming

#include <stdio.h>

int main() {
int low, high, i, flag, temp;
printf("Enter two numbers(intervals): ");
scanf("%d %d", &low, &high);

// swap numbers if low is greather than high
if (low > high) {
temp = low;
low = high;
high = temp;
}

printf("Prime numbers between %d and %d are: ", low, high);
while (low < high) {
flag = 0;

// ignore numbers less than 2
if (low <= 1) {
++low;
continue;
}

for (i = 2; i  < = low / 2; ++i) {
if (low % i == 0) {
flag = 1;
break;
}
}
if (flag == 0)
printf("%d ", low);
++low;
}

return 0;
}
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