trying to learn from c to c++

[congiants2]

Can someone help me write this code to c++. I wanted to see how hard it was to self teach c++ from only knowing basic c.

*************

#include <stdio.h> /*included to allow for printf()/scanf() to be used*/
#include <time.h> /*included to allow time() to be used*/
#include <stdlib.h> /*include to allow rand() and srand() to be used*/


int main(void){

int x, user, guess; /* variable to hold our random integer*/

srand(time(NULL)); /*seeds random number generator. Do this just once*/

x = rand()%51;
printf("What number do you think I chose?: \n");

for(guess=0; guess<5; guess++){
scanf("%d", &user);

if(user>x){
printf("The number is lower than that\n");
}
else if(user<x){
printf("The number is higher than that\n");
}
else if(user==x){
printf("YOU GOT IT!\n");
break;
}

}

return 0;
}

[JLBorges]

For starters:

//#include <stdio.h>	/*included to allow for printf()/scanf() to be used*/
//#include <time.h>	/*included to allow time() to be used*/
//#include <stdlib.h>	/*include to allow rand() and srand() to be used*/
#include <cstdio>
#include <ctime>
#include <cstdlib> // these are the equivalent C++ headers

// int main(void){
int main() { // preferred C++ style

    // int x, user, guess;	 /* variable to hold our random integer*/
    // in C++, we define variables close to their point of use.
    // in particular, we do not define a variable till we know how to initialize it

    // srand(time(NULL)); /*seeds random number generator. Do this just once*/
    std::srand( std::time(nullptr) ) ; // or std::srand( std::time(0) ) ;
    // standard library entities are in namespace std

    // x = rand()%51;
    enum { UPPER_BOUND = 51, MAX_GUESSES = 5 } ; // we try to avoid magic numbers
    const int x = std::rand() % UPPER_BOUND ; 

    // printf("What number do you think I chose?: \n");
    std::printf("What number do you think I chose?: \n");

    // for(guess=0; guess<5; guess++){
    for( int guess = 0 ; guess < MAX_GUESSES ; ++guess ) {
        // we prefer using the prefix ++ over the postfix ++
        // scanf("%d", &user);
        int user ; std::scanf( "%d", &user ) ;

        if( user>x ){
            // printf("The number is lower than that\n");
            std::printf("The number is lower than that\n");
        }
        else if(user<x){
            // printf("The number is higher than that\n");
            std::printf("The number is higher than that\n");
        }
        //else if(user==x){
        else { // user== x if both the earlier checks yielded false
            // printf("YOU GOT IT!\n");
            std::printf("YOU GOT IT!\n");
            break;
        }
    }
     // return 0 ;
     // not required in C++; if there is no return statement, return 0 is assumed
}

After a while:

#include <iostream>
#include <ctime>
#include <random>

int main()
{
    enum { MIN_VALUE = 0, MAX_VALUE = 51, MAX_GUESSES = 5 } ;
    std::mt19937 rng( std::time(nullptr) ) ;
    std::uniform_int_distribution<> distr( MIN_VALUE, MAX_VALUE ) ;
    const int x = distr(rng) ;

    std::cout << "What number do you think I chose?: " ;

    for( int guess = 0 ; guess < MAX_GUESSES ; ++guess )
    {
        int user ; std::cin >> user ;

        if( user > x ) std::cout << "The number is lower than that\n" ;
        else if( user < x ) std::cout << "The number is higher than that\n" ;
        else { std::cout << "YOU GOT IT!\n" ; break ; }
    }
}

[o1vk4iN6]

You aren't exactly scratching the surface of C++ if you are just porting code from C, no new features or techniques.