// C program to build the complete
// snake game
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <conio.h>

int i, j, height = 20, width = 20;
int gameover, score;
int x, y, fruitx, fruity, flag;

// Function to generate the fruit
// within the boundary
void setup()
{
	gameover = 0;

	// Stores height and width
	x = height / 2;
	y = width / 2;
label1:
	fruitx = rand() % 20;
	if (fruitx == 0)
		goto label1;
label2:
	fruity = rand() % 20;
	if (fruity == 0)
		goto label2;
	score = 0;
}

// Function to draw the boundaries
void draw()
{
	system("cls");
	for (i = 0; i < height; i++) {
		for (j = 0; j < width; j++) {
			if (i == 0 || i == width - 1
				|| j == 0
				|| j == height - 1) {
				printf("#");
			}
			else {
				if (i == x && j == y)
					printf("0");
				else if (i == fruitx
						&& j == fruity)
					printf("*");
				else
					printf(" ");
			}
		}
		printf("\n");
	}

	// Print the score after the
	// game ends
	printf("score = %d", score);
	printf("\n");
	printf("press X to quit the game");
}

// Function to take the input
void input()
{
	if (kbhit()) {
		switch (getch()) {
		case 'a':
			flag = 1;
			break;
		case 's':
			flag = 2;
			break;
		case 'd':
			flag = 3;
			break;
		case 'w':
			flag = 4;
			break;
		case 'x':
			gameover = 1;
			break;
		}}
}

// Function for the logic behind
// each movement
void logic()
{
	sleep(0.01);
	switch (flag) {
	case 1:
		y--;
		break;
	case 2:
		x++;
		break;
	case 3:
		y++;
		break;
	case 4:
		x--;
		break;
	default:
		break;
	}

	// If the game is over
	if (x < 0 || x > height
		|| y < 0 || y > width)
		gameover = 1;

	// If snake reaches the fruit
	// then update the score
	if (x == fruitx && y == fruity) {
	label3:
		fruitx = rand() % 20;
		if (fruitx == 0)
			goto label3;

	// After eating the above fruit
	// generate new fruit
	label4:
		fruity = rand() % 20;
		if (fruity == 0)
			goto label4;
		score += 10;
	}
}

// Driver Code
void main()
{
	int m, n;

	// Generate boundary
	setup();

	// Until the game is over
	while (!gameover) {

		// Function Call
		draw();
		input();
		logic();
	}
}
by

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#include <stdio.h>
int main()
{
    char name[50];
    printf("Enter name:");
    scanf("%s", name);
    printf("Hello %s \n" , name );
    return 0;
    
}

About C

C language is one of the most popular general-purpose programming language developed by Dennis Ritchie at Bell laboratories for UNIX operating system. The initial release of C Language was in the year 1972. Most of the desktop operating systems are written in C Language.

Key features:

  • Structured Programming
  • Popular system programming language
  • UNIX, MySQL and Oracle are completely written in C.
  • Supports variety of platforms
  • Efficient and also handle low-level activities.
  • As fast as assembly language and hence used as system development language.

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);

Arrays

Array is a collection of similar data which is stored in continuous memory addresses. Array values can be fetched using index. Index starts from 0 to size-1.

Syntax

One dimentional Array:

data-type array-name[size];

Two dimensional array:

data-type array-name[size][size];

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.

Two types of functions are present in C

  1. Library Functions:

Library functions are the in-built functions which are declared in header files like printf(),scanf(),puts(),gets() etc.,

  1. User defined functions:

User defined functions are the ones which are written by the programmer based on the requirement.

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
}