diff --git a/contribution/jowinjohnchemban/checkifsumofprime.c b/contribution/jowinjohnchemban/checkifsumofprime.c new file mode 100644 index 00000000..31cdbe08 --- /dev/null +++ b/contribution/jowinjohnchemban/checkifsumofprime.c @@ -0,0 +1,77 @@ +#include +#include +#include +#include //WINDOWS + + +int checkPrime(int n); + +int main() +{ + int n, i, flag = 0; + + system("CLS"); + printf("\n\n\n"); + printf("\n\t ######################################"); + printf("\n\t # #"); + printf("\n\t # CHECK A NUMBER #"); + printf("\n\t # REPRESENTED AS #"); + printf("\n\t # SUM OF TWO PRIME NUMBERS #"); + printf("\n\t # #"); + printf("\n\t ######################################\n"); + + Sleep(2000); + system("CLS"); + + printf("\n Enter a positive integer : "); + scanf("%d", &n); + printf("\n"); + + + for(i = 2; i <= n/2 && !kbhit() ; ++i) + // iterate till i=n/2 and there is no key pressed - interupt + { + // condition for i to be a prime number + if (checkPrime(i) == 1) + { + // condition for n-i to be a prime number + if (checkPrime(n-i) == 1) + { + // n = primeNumber1 + primeNumber2 + printf(" %d = %d + %d\n", n, i, n - i); + flag = 1; + } + + } + } + + printf("\a"); + if (flag == 0) + printf(" %d cannot be expressed as the sum of two prime numbers.\a", n); + // cannot expressed as sum of two prime numbers + + + getch(); + system("CLS"); + return 0; + // EXIT +} + +// Function to check prime number +int checkPrime(int n) +{ + int i, isPrime = 1; + + for(i = 2; i <= n/2; ++i) + { + if(n % i == 0) + { + isPrime = 0; + break; + } + } + + return isPrime; +} + + diff --git a/contribution/jowinjohnchemban/prime.c b/contribution/jowinjohnchemban/prime.c new file mode 100644 index 00000000..13cb2379 --- /dev/null +++ b/contribution/jowinjohnchemban/prime.c @@ -0,0 +1,24 @@ + #include + +int main(){ + + int num,i,count,n; + printf("Enter max range: "); + scanf("%d",&n); + + for(num = 1;num<=n;num++){ + + count = 0; + + for(i=2;i<=num/2;i++){ + if(num%i==0){ + count++; + break; + } + } + + if(count==0 && num!= 1) + printf("%d,",num); + } + return 0; +}