// C++ Program to Implement Rock-Paper-Scissors 
#include <cstdlib> 
#include <ctime> 
#include <iostream> 
using namespace std; 

// get the computer move 
char getComputerMove() 
{ 
	int move; 
	// generating random number between 0 - 2 
	srand(time(NULL)); 
	move = rand() % 3; 

	// returning move based on the random number generated 
	if (move == 0) { 
		return 'p'; 
	} 
	else if (move == 1) { 
		return 's'; 
	} 
	return 'r'; 
} 

// Function to return the result of the game 
int getResults(char playerMove, char computerMove) 
{ 
	// condition for draw 
	if (playerMove == computerMove) { 
		return 0; 
	} 

	// condition for win and loss according to game rule 
	if (playerMove == 's' && computerMove == 'p') { 
		return 1; 
	} 
	if (playerMove == 's' && computerMove == 'r') { 
		return -1; 
	} 
	if (playerMove == 'p' && computerMove == 'r') { 
		return 1; 
	} 
	if (playerMove == 'p' && computerMove == 's') { 
		return -1; 
	} 
	if (playerMove == 'r' && computerMove == 'p') { 
		return -1; 
	} 
	if (playerMove == 'r' && computerMove == 's') { 
		return 1; 
	} 
	
	return 0; 
} 

// driver code 
int main() 
{ 

	char playerMove; 

	cout << "\n\n\n\t\t\tWelcome to Stone Paper Scissor "
			"Game\n"; 

	cout << "\n\t\tEnter r for ROCK, p for PAPER, and s "
			"for SCISSOR\n\t\t\t\t\t"; 

	// input from the user 
	while(1) { 
		cin >> playerMove; 
		if (playerMove == 'p' || playerMove == 'r' || playerMove == 's') { 
			break; 
		} 
		else { 
			cout << "\t\t\tInvalid Player Move!!! Please Try Again." << endl; 
		} 
	} 
	
	

	// computer move 
	char computerMove = getComputerMove(); 

	int result = getResults(playerMove, computerMove); 

	// priting result based on who won the game 
	if (result == 0) { 
		cout << "\n\t\t\tGame Draw!\n"; 
	} 
	else if (result == 1) { 
		cout << "\n\t\t\tCongratulations! Player won the "
				"game!\n"; 
	} 
	else { 
		cout << "\n\t\t\tOh! Computer won the game!\n"; 
	} 

	// showing both moves 
	cout << "\t\t\tYour Move: " << playerMove << endl; 
	cout << "\t\t\tComputer's Move: " << computerMove << endl; 

	return 0; 
}

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#include <iostream>
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using namespace std;

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    string name;
    cout << "Enter name:";
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    cout << "Hello " << name;
    return 0;
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About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}