Paper, rock, scissor game

[iamnoob15]

I just wrote a program for Paper, rock, scissor game.

Is this correct?

#include <iostream>
using namespace std;

int main()
{
char a,b;

cout<<"p = paper"<<endl;
cout<<"r = rock"<<endl;
cout<<"s = scissor"<<endl;

cout<<"Player 1 choose"<<endl;
cin>>a;

cout<<"Player 2 choose"<<endl;
cin>>b;


if ((a=='r') && (b=='r') || (a=='p') && (b=='p') || (a=='s') && (b=='s') )
{
cout<<"tie";
}

else if ((a=='p') && (b=='r') || (a=='r') && (b=='s') || (a=='s') && (b=='p') )
{
cout<<"Player 1 won";
}
else if ((a=='r') && (b=='p') || (a=='s') && (b=='r') || (a=='p') && (b=='s') )
{
cout<<"Player 2 won";
}
}

[IceThatJaw]

Add a line of validation to check if the player selected a correct move and then just compare if a = b for the tie check so it reads better.

[a4q16]

this condition is sufficient for tie

if(a==b)
   std::cout<<"tie"<<std::endl;

[giblit]

else if ((a=='r') && (b=='p') || (a=='s') && (b=='r') || (a=='p') && (b=='s') ) This should be else if ((a=='r' && b=='p') || (a=='s' && b=='r') || (a=='p' && b=='s') ) The first one needs to be similar also. Btw you could just do an else for the tie.

[shadder]

to make the game more versatile you also have to account human error.....
like

if(a!='r' || a!='p' || a!='s' )
cout<<"invalid";//etc........ 

then you can create a loop to re-enter input.......

[Disch]

@programmer007:

if(a!='r' || a!='p' || a!='s' )

This condition will always be true.

You probably wanted && here instead of ||.

Although any time you are stringing together a bunch of &&s or ||s you should probably reconsider your approach. There is usually a better way.


EDIT:

for instance this:

if ((a=='r') && (b=='r') || (a=='p') && (b=='p') || (a=='s') && (b=='s') )
// tie 

is largely redundant. You could greatly simplify this like so:

if(a == b)
// tie 

[shadder]

@disch

what if the user puts an input not expected by program???

[cire]

Validating input should not be part of the game logic. That should be done (if it's going to be done) prior to the first if condition.

[dhayden]

To make the logic easier, convert the user's input to lower (or upper) case. You'll also want to validate it as others have said. You could put all this in a function:

bool normalize(char &c)
{
    c = tolower(c);
    return c == 'r' || c == 'p' || c == 's';
}

You might also put the logic for a winner into a function:

// Return true if FIRST beats SECOND. Both parameters must be normalized
// (i.e., either 'r', 'p' or 's')
firstIsWinner(char first, char second)
{
    return  first=='p' && second=='r' || first=='r' && second=='s' || first=='s' && second=='p';
}

Now your main logic gets easier and your code can double check itself:

cout<<"Player 1 choose"<<endl;
cin>>a;
if (!normalize(a)) return 1;

cout<<"Player 2 choose"<<endl;
cin>>b;
if (!normalize(b)) return 1;

if (a ==b )
{
    cout<<"tie";
}
else if (firstIsWinner(a,b) )
{
    cout<<"Player 1 won";
}
else if (firstIsWinner(b,a) )
{
    cout<<"Player 2 won";
} else {
    cout << "Logic error!";
}
return 0;

[iamnoob15]

I thank you all. :)

[jasonwynn10]

try this too:

#include <iostream>
#include <windows.h>
#include <string>
using namespace std;

char a,b;
string PLAYER_1,PLAYER_2;
string YN;
int x;
int main()
{
while(x!=1){
cout << "Enter your name:"<<endl;
cin >> PLAYER_1;
cout << "Enter your name:"<<endl;
cin >> PLAYER_2;
system("cls");

cout<<"P = paper"<<endl;
cout<<"R = rock"<<endl;
cout<<"S = scissor"<<endl;

cout<<"Player 1 choose"<<endl;
cin>>a;
system("cls");

cout<<"P = paper"<<endl;
cout<<"R = rock"<<endl;
cout<<"S = scissor"<<endl;

cout<<"Player 2 choose"<<endl;
cin>>b;
system("cls");

if ((a=='r'||a=='R') && (b=='r'||b=='R') || (a=='p'||a=='P') && (b=='p'||b=='P') || (a=='s'||a=='S') && (b=='s'||b=='S') )
{
cout<<"\n\n\n\n\n\n\n\n\n\n\n                                                   "<<PLAYER_1<<" and "<<PLAYER_2<<" TIE!";
}

else if ((a=='p'||a=='P') && (b=='r'||b=='R') || (a=='r'||a=='R') && (b=='s'||b=='S') || (a=='s'||a=='S') && (b=='p'||b=='P') )
{
cout<<"\n\n\n\n\n\n\n\n\n\n\n                                                   "<< PLAYER_1 <<" WON!";
}
else if ((a=='r'||a=='R') && (b=='p'||b=='P') || (a=='s'||a=='S') && (b=='r'||b=='R') || (a=='p'||a=='P') && (b=='s'||b=='S') )
{
cout<<"\n\n\n\n\n\n\n\n\n\n\n                                                   "<< PLAYER_2 <<" WON!\n";
}else cout << "Logic Error!";
cout << "\nHit the spacebar to play again";
Sleep(2000);
if(GetAsyncKeyState(VK_SPACE)){
    system("cls");
}else{x=1;}}
system("cls");
cout << "Ending program in 2 seconds";
Sleep(2000);
system("cls");
system("exit");
}

[giblit]

Please use indentations.

if ((a=='r'||a=='R') && (b=='r'||b=='R') || (a=='p'||a=='P') && (b=='p'||b=='P') || (a=='s'||a=='S') && (b=='s'||b=='S') )
{
cout<<"\n\n\n\n\n\n\n\n\n\n\n                                                   "<<PLAYER_1<<" and "<<PLAYER_2<<" TIE!";
}

there are much better ways to check if it is a tie. Such as if neither player won then it is a tie. Or something like if(a == b) or better yet if(toupper(a) == toupper(b))

Check out his way http://www.cplusplus.com/forum/beginner/141476/#msg747686

[jasonwynn10]

kk

[novellof]

You don't have to right the tie statement. Think about it. If player 1 doesn't win.. and if player 2 doesn't win...then ...ELSE {cout << "tie" ; }

[jasonwynn10]

If player 1 doesn't win.. and if player 2 doesn't win...then ...ELSE {cout << "tie" ; }

It could also be a logic error

[giblit]

Technically speaking logic error shouldn't be within the game conditions. That should be checked while you get the input. I think I also mentioned the else on my earlier post. http://www.cplusplus.com/forum/beginner/141476/#msg747290