How can I get the value from a memory address?

I want to get the value from a memory address which I have without crashing the program.

here is my code:

int main(){
    int *ptr=(int*)0x09D37570;
    while(1){
        system("cls");
        cout<<(*ptr);
    }
    return 0;
}

but that crashes the program, it crashes by calling *ptr, why does that happen? how can i get the value without problems?

Answer

Every process has its own memory space, the same address in different processes maps different physical address, so it is meaningless to do like that.