Sum of prime numbers from 1 to 100 in c





C program to get sum of prime numbers from 1 to 100 


#include<stdio.h>
int main(){

    int num,i,count,sum=0;

    for(num = 1;num<=100;num++){

         count = 0;

         for(i=2;i<=num/2;i++){
             if(num%i==0){
                 count++;
                 break;
             }
        }
        
         if(count==0 && num!= 1)
             sum = sum + num;
    }

    printf("Sum of prime numbers is: %d ",sum);
  
   return 0;
}
  
Output:
Sum of prime numbers is: 1060


Algorithm:


Definition of prime number:

A natural number greater than one which has not any other divisors except 1 and itself is called prime number. In other word we can say which has only two divisors 1 and number itself. For example: 5

Their divisors are 1 and 5.

Note: 2 is only even prime number.

Logic for prime number in c
We will take a loop and divide number from 2 to number/2. If the number is not divisible by any of the numbers then we will print it as prime number.

Example of prime numbers : 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199 etc.




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