C++ My program has confused me greatly [closed] - c++

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Here it is:
#include <iostream>
#include <cstdlib> // for rand() and srand()
#include <ctime>
using namespace
int main()
{
//cout << "How many players?" << endl;
int numplayers=1;
//cin >> numplayers;
int players[numplayers];
int x=0,y=0;
srand(time(0));
x=(rand() % 6 + 1);
y=(rand() % 6 + 1);
players[1]=players[1]+x+y;
cout << ("Your score is" + players[1]) << endl;
cin >> numplayers;
}
Ok My original problem was that this always crashed, now it prints "#"???

Answer 1

C++ arrays are 0 based.
players[1] is accessing a location outside the range of the array.
You will want: players[0].

Answer 2

cout << ("Your score is" + players[1]) << endl;
Here you're trying to use direct string concatenation, but you can't concatenate a string literal with an integer like that. You end up doing pointer arithmetic, which is definitely not what you intended.
You should instead use cout's built-in formatting:
cout << "Your score is" << players[1] << endl;
Your next problem is that players is not declared correctly; an array cannot have runtime bounds, and numplayers (despite having only the one initial value) is ultimately a "runtime" variable. You would be better off with a std::vector if the size of the array is going to change later; otherwise make numplayers a constexpr.
Your last problem is that, if the array declaration were valid, you'd be trying to access the second element of a one-element array! The first element is players[0], not players[1].

Answer 3

There are many things you're doing not good.
I believe you're using C++, there is no known way to me about creating arrays of dynamic size i.e. int players[numplayers]. In C++ either we can create array of fixed size i.e. int players[10] or use pointer to an array for dynamically allocated memory e.g. int* players = new int[numplayers]. This allocates an array of size numplayers and an int pointer named players is pointing to it. We can use this pointer as normal array e.g. printing 1st index of array is written as player[0] or another syntax is *(player + 0). Remember to delete this dynamically allocated memory at the end of program i.e. delete[] player.
Second thing is when you have allocated an array and are using its value for computation, always initialize it to 0 as newly allocated array contains garbage value and it will affect your computations. code for initializing it to zero may be like this:
Here is the loop:
for(int i = 0 ; i < numplayers ; i++){
player[i]=0;
//another syntax is : *(player + i) = 0;
}
C++ does not concat as you did in your std::cout statement. Make it like this:
cout << "Your score is" << players[0] << endl;
In C++, arrays always start with index zero, so 1st index will be 0 in this case. So your program will work well if it is like this:
int numplayers = 1;
int* players = new int[numplayers];
int x = 0, y = 0;
srand(time(0));
x = (rand() % 6 + 1);
y = (rand() % 6 + 1);
players[0] = 0;
players[0] = players[0] + x + y;
cout << "Your score is" << players[0] << endl;
delete[] players;
return 0;

Answer 4

Definitely it crashes for the below line:
players[1]=players[1]+x+y;
Because size of players array is 1, so it has only index 0. And in above line, it tries to access index 1. Take a look at Buffer Overflow and array index out of bounds.
Try to define an array with constant size.
If you need a dynamic array, use linked list or vector.