The Snake Game in C++

It is similar to the game which was very common in mobiles few years back. The snake eats food items to increase its length and tries to avoid obstacles in order to win the game. The game has 3 modes- easy, normal and hard. Hard mode has the maximum number of obstacles. The obstacles and food items are generated at random so every time the game is different from the last time. 

The source code is given below-

#include<iostream.h>
#include<conio.h>
#include<process.h>
#include<time.h>
#include<stdlib.h>
//created by Aditya Vijayvergia 
//uploaded at thecodingedge.blogspot.com
int snake[40][2],point[20][2],dead[200][2],nd,len,n=20,m=39,pos[2];
void create()
{
   int i;
   len=5;
   srand(time(NULL));
   for(i=0;i<len;i++)
       {
  snake[i][1]=i;
       }
   for(i=0;i<20;i++)
      {
  point[i][0]=rand() %20;
  point[i][1]=rand() %40;
      }
   srand(time(NULL));
   for(i=0;i<nd;i++)
      {
  dead[i][0]=rand() %20;
  dead[i][1]=rand() %40;
      }
}

int found(int x,int y)
{
for(int i=0;i<len;i++)
   if(snake[len-1][0]==x&&snake[len-1][1]==y)
     return 2;

   else if(snake[i][0]==x&&snake[i][1]==y)
     return 1;
return 0;
}

int ifdead(int x,int y)
{

   for(int j=0;j<nd;j++)
   if(dead[j][0]==x&&dead[j][1]==y)
       return 1;
   return 0;
}
int ifpoint(int x,int y)
{
   for(int i=0;i<20;i++)
   {
   if(point[i][0]==x&&point[i][1]==y)
      return 1;
   }
   return 0;
}

void show()
{
   //cout<<"show running";
   clrscr();
   cout<<"\n";
   for(int k=0;k<m+1;k++)
   cout<<"__";
   cout<<"\n";
   for(int i=0;i<n;i++)
   {
   cout<<"|";
   for(int j=0;j<m;j++)
   {
       if(found(i,j)==2)
       cout<<" m";
       else if(found(i,j)==1)
       cout<<" o";
       else if(ifpoint(i,j))
       cout<<" *";
       else
       if(ifdead(i,j))
       cout<<" X";
       else
       cout<<"  ";
   }
   cout<<"|";
   }
   for(k=0;k<m+1;k++)
   cout<<"__";
}

void changepoint(int x,int y)
{
   for(int i=0;i<20;i++)
   if(point[i][0]==x&&point[i][1]==y)
   {
       point[i][0]=-1;
       point[i][1]=-1;
   }
}


void move(int x,int y)
{
    x=(x+n)%n;
    y=(y+m)%m;
    if(ifpoint(x,y))
    {
  pos[0]=x;
  pos[1]=y;
  changepoint(x,y);

    }
    else
    if(ifdead(x,y))
    {
      clrscr();
      cout<<"\n\n\n\t\tGAME OVER\n\n\t\tScore:"<<len-5;

      getch();
      exit(0);
    }
    for(int i=0;i<len-1;i++)
    for(int j=0;j<2;j++)
       snake[i][j]=snake[i+1][j];
    snake[i][0]=x;
    snake[i][1]=y;
    //}
    show();

    if(snake[len-1][0]==pos[0]&&snake[len-1][1]==pos[1])
    {
 len++;
  if(len-5==20)
  {
     clrscr();
     cout<<"\n\n\n\t\tVICTORY";
     exit(0);
  }
 for(i=len-1;i>0;i--)
 for(j=0;j<2;j++)
     snake[i][j]=snake[i-1][j];
 snake[0][0]=pos[0];
 snake[0][1]=pos[1];
 pos[0]=-1;
 pos[1]=-1;
    }
}

void menu()
{
   int choice;
   cout<<"\n\n\tSANKE GAME";
   cout<<"\n\n\n1.easy\n2.normal\n3.hard";
   cin>>choice;
   switch(choice)
   {

   case 1:nd=50;
   break;
   case 2:nd=125;
   break;
   case 3:nd=200;
   break;
   }
}

void main()
{
    clrscr();
    menu();
    create();
    show();
    pos[0]=-1;
    pos[1]=-1;
    char m;
    while(1)
    {
    cout<<"\n\t\t";
    cout<<"enter choice:";
    cin>>m;
    switch(m)
    {
    case 'd':move(snake[len-1][0],snake[len-1][1]+1);
      break;
    case 'w':move(snake[len-1][0]-1,snake[len-1][1]);
      break;
    case 's':move(snake[len-1][0]+1,snake[len-1][1]);
      break;
    case 'a':move(snake[len-1][0],snake[len-1][1]-1);
      break;
    case 'p':exit(0);
    }
    }
}

Sample output is given below.

Generating permutations in Java using array

The following code generates all possible permutations till the entered integer integers. Similar program can be made to permute the characters of a string.

Explanation:
First we enter only 1 in a array.
Then for entering 2 we have two choices- before 1 and after 1 as- "21" and "12".
The program uses recursion so for "21" we can add 3 at 3 different places as "321", "231" and "213" i.e., at first position, between them and in the last position.

The code is given below: 

import java.util.Arrays;
import java.util.Scanner;

/**
 *
 * @author Aditya Vijayvergia @ thecodingedge.blogspot.com
 */
public class GeneratingPermutations {

    static int perm(int []a,int n,int m)
    {                          //n=the element that is being added in this recursive call
        int []b=new int[m];    //m=total no of elemets
        for(int i=0;i<n;i++)
            {
                System.arraycopy(a, 0, b, 0, m);//copy the state of array a to array b
                for(int j=n-1;j>i;j--)//shift values 1 step ahead
                    b[j]=b[j-1];
                b[i]=n;//store n at the empty location
                if(n==m)
                {
                    System.out.println(Arrays.toString(b));
                }
                else{    
                    perm(b,n+1,m);   
                    }
            }
        return 0;
    }
    
    public static void main(String[] args) {
        int m;
        System.out.print("enter the number of elements:");
        Scanner in=new Scanner(System.in);
        m=in.nextInt();
        int []a=new int[m];
        perm(a,1,m);
    }
}

Sample Output:

Maze Solving Algorithm

This maze solving algorithm works on the principle of Backtracking. It is implemented in Java.

The main idea is to solve the problem is move from the starting point in all the possible directions until we reach the goal. While moving in a particular direction, when ever the path splits(i.e., a node is encountered) one of the path is chosen. We move on the same path until we encounter a dead end(or a leaf). When a leaf is reached, we backtrack to the last encountered node and chose another path. This procedure is followed recursively until either we reach the goal or we reach the first encountered node again by backtracking from all possible ways and hence no solution to the maze exists. When we have reached our goal, we can mark the path used.

The code is explained with comments. Further for better understanding, i have used some print statements as comments. The code can be tested on other maze problem too by simply changing the maze array used in the code.

Open link to go to View Source Code.
Click here to download class file.

The output of the code is given under:

   

Tic-Tac-Toe Application in Java using Applet

The application runs with all the rules and it also checks which player (Blue or Red) wins. Moreover it keeps a record of the number of games won by the players. After each game the result is shown and the next game starts automatically with the score of all the previous games. In addition to the the buttons, the application also maintains an 3x3 array in order to check if a game is won or  drawn.


View Source Code
Download class file

Some of the screen shots of the application are given below.

Typing Speed Calculator Application in Java using Applet

This application calculates your typing speed. A text is shown and the amount of text you can copy in 1 minute determines your typing speed.

This application is unique as instead of using the traditional methods of using threads in applets, I have used the concept of inner classes. There are two inner classes in the main class. One class called SetFrame class extends from Frame class and the other class called Timer class extends from thread class. As the name suggests, SetFrame class creates the applet and the Timer class displays the time left.   

View Source Code
Download class file

Some screen shots of the application are given below.