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@jatinsharrma
Created March 27, 2019 17:59
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Find prime number to a specific number
//this program takes alot of memory if given number is big. Can optimize it by using dynamic array concept
#include <stdio.h>
int print(int p[], int index){
for(int i =0; i<index;i++){
printf("%d\n",p[i]);
}
}
int prime(int x){
int p[x/2+1];
int index =2;
if (x>3){
p[0] = 2;
p[1] = 3;
for (int i = 4 ; i<=x;i++){
if (i%2 == 0){
continue;
}
else{
for (int j=0 ;j<index;j++){
if(i%p[j]==0){
break;
}
if (j == (index-1)){
p[index] = i;
index ++;
}
}
}
}
print(p,index);
}
else if (x == 3){
p[0]=2;
p[1]=3;
index = 2;
print(p,index);
}
else if (x == 2){
p[0] = 2;
index = 1;
print(p,index);
}
else{
printf("No prime found. You entered a invalid range");
}
}
void main() {
prime(1);
}
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