Q:

Same output no matter the input

So I'm writing this program to be a two player game of paper rock scissors, and no matter what each player chooses, the output is "Player 1 wins." 
#include <stdio.h>
int main(void)
{
long player1Choice, player2Choice, p, r, s;

        printf("Player 1, enter paper (p), rock (r), or scissors (s)\n");
            player1Choice=getchar();
            getchar();

        printf("Player 2, enter paper (p), rock (r), or scissors (s)\n");
            player2Choice=getchar();
            getchar();

        if((player1Choice=p)&&(player2Choice=r))    
            printf("Player 1 wins!\n");
        else if((player1Choice=r)&&(player2Choice=p))
            printf("Player 2 wins!\n");
        else if((player1Choice=r)&&(player2Choice=s))
            printf("Player 1 wins!\n");
        else if((player1Choice=s)&&(player2Choice=r))
            printf("Player 2 wins!\n");
        else if((player1Choice=s)&&(player2Choice=p))
            printf("PLayer 1 wins!\n");
        else if((player1Choice=p)&&(player2Choice=s))
            printf("Player 2 wins!\n");

    printf("Press any key to exit");
    getchar();
    return 0;
}

I think the logical "and"s in my "if" statements may be causing the trouble, but I'm not sure.

A:

You have declared p, r, and s, but you never initialize them.  You also are using assignment (=) rather than a test for equality (==). Your program causes undefined behaviour.  It looks like you intended something along the lines of:
if ((player1Choice == 'p') && (player2Choice == 'r'))

After fixing those, you can get rid of the spurious variables.  Alternately, change your variable declarations to include initialization:
long player1Choice, player2Choice, p = 'p', r = 'r', s = 's';

You'll still need to fix your = problem.
You should turn more warnings on in your compiler.  For example, for your program, from Clang:
$ clang -Wall example.c -o example
example.c:19:51: warning: variable 's' is uninitialized when used here
      [-Wuninitialized]
        else if((player1Choice=r)&&(player2Choice=s))
                                                  ^
example.c:4:43: note: initialize the variable 's' to silence this warning
long player1Choice, player2Choice, p, r, s;
                                          ^
                                           = 0
example.c:15:27: warning: variable 'p' is uninitialized when used here
      [-Wuninitialized]
        if((player1Choice=p)&&(player2Choice=r))    
                          ^
example.c:4:37: note: initialize the variable 'p' to silence this warning
long player1Choice, player2Choice, p, r, s;
                                    ^
                                     = 0
example.c:15:46: warning: variable 'r' is uninitialized when used here
      [-Wuninitialized]
        if((player1Choice=p)&&(player2Choice=r))    
                                             ^
example.c:4:40: note: initialize the variable 'r' to silence this warning
long player1Choice, player2Choice, p, r, s;
                                       ^
                                        = 0
3 warnings generated.

