C Program to Print Maximum Prime Number Between 1 to N

In this example, you will learn print maximum prime number between 1 to n (entered by the user). The user will enter 100 input number and program will check all prime numbers till 100 and print highest prime number among them.

A prime is a number that is divisible only by itself and 1 (e.g. 2, 3, 5, 7, 11)

Input: 100
Output: 97 (Because 97 is the highest prime between 1 to 100)

1 2	Input: 100 Output: 97 (Because 97 is the highest prime between 1 to 100)

Example: Maximum Number Between 1 to N

#include<stdio.h>
int main()
{
    int num,i;
    int count = 0,j,maxPrime = 1;
    printf("Enter a number: ");
    scanf("%d",&num);
    for(i = 1; i <= num; i++) 
    {
        count = 0;
        for(j = 1; j <= i; j++) 
        {
            if(i % j == 0) 
            {
                count++;
            }
        }
        if(count == 2) 
        {
            if(maxPrime < i)    
            {
                maxPrime = i;
            }
        }
    }
    printf("Maximum Prime number between 1 to %d is %d\n",num,maxPrime);
    //exit status
    return 0;
}

#include<stdio.h>

int main()

{

int num,i;

int count = 0,j,maxPrime = 1;

printf("Enter a number: ");

scanf("%d",&num);

for(i = 1; i <= num; i++)

{

count = 0;

for(j = 1; j <= i; j++)

{

if(i % j == 0)

{

count++;

}

if(count == 2)

{

if(maxPrime < i)

{

maxPrime = i;

}

printf("Maximum Prime number between 1 to %d is %d\n",num,maxPrime);

//exit status

return 0;

}

When you run the program, the output will be following:

Enter a number: 100                                                                                                            
Maximum Prime number between 1 to 100 is 97

1 2	Enter a number: 100 Maximum Prime number between 1 to 100 is 97