#include <stdio.h>
int main(){
    int a=10;
    int *ptr;
    ptr=&a
    printf("value of ptr:%d\n",a);
    int arr[3]={10,20,30};
    int *p=arr;
    for(int i=0;i<3;i++)
    {
        printf("arithmetic:%d\n",i,*(p+1));
    }
    p++
    printf("value to arr[i]:%d\n",*p);
    p++;
    printf("value to arr[2]:%d\n",*p);
}