Read and learn the source code, and made simple comments and modifications, which only used linked list data structure, very suitable for beginners of C language learning to read.
The program can be compiled and run under VS2013.
#include<stdio.h>
#include<time.h>
#include<windows.h>
#include<stdlib.h>
#define U 1
#define D 2
#define L 3
#define R 4 // The state of the snake, U On: ; D : under; L: On the left R Right:
typedef struct SNAKE // The snake 1 A node
{
int x;
int y;
struct SNAKE *next;
}snake;
// The global variable //
int score = 0, add = 10;// Total score and food score per meal.
int status, sleeptime = 200;// The time interval for each run
snake *head, *food;// Snake head pointer, food pointer
snake *q;// The pointer used to traverse the snake
int endGamestatus = 0; // At the end of the game, 1 : hit a wall; 2 : bite yourself; 3 : quit the game voluntarily.
// Declare all functions //
void Pos();
void creatMap();
void initSnake();
int biteSelf();
void createFood();
void cantCrossWall();
void snakeMove();
void pause();
void runGame();
void initGame();
void endGame();
void gameStart();
void Pos(int x, int y)// Set cursor position
{
COORD pos;
HANDLE hOutput;
pos.X = x;
pos.Y = y;
hOutput = GetStdHandle(STD_OUTPUT_HANDLE);// Returns a handle to a standard input, output, or error device / Handle to the error screen buffer
SetConsoleCursorPosition(hOutput, pos);
}
void creatMap()// Create a map
{
int i;
for (i = 0; i<58; i += 2)// Print top and bottom border
{
Pos(i, 0);
printf(" s ");//1 Two squares take up two positions
Pos(i, 26);
printf(" s ");
}
for (i = 1; i<26; i++)// Print left and right border
{
Pos(0, i);
printf(" s ");
Pos(56, i);
printf(" s ");
}
}
void initSnake()// Initializes the snake body
{
snake *tail;
int i;
tail = (snake*)malloc(sizeof(snake));// Start with the tail of the snake x,y Set the starting position //
tail->x = 24;
tail->y = 5;
tail->next = NULL;
for (i = 1; i <= 4; i++)// The initial length is 4
{
head = (snake*)malloc(sizeof(snake));
head->next = tail;
head->x = 24 + 2 * i;
head->y = 5;
tail = head;
}
while (tail != NULL)// From head to toe, output snake body
{
Pos(tail->x, tail->y);
printf(" s ");
tail = tail->next;
}
}
//??
int biteSelf()// Judge if you bit yourself
{
snake *self;
self = head->next;
while (self != NULL)
{
if (self->x == head->x && self->y == head->y)
{
return 1;
}
self = self->next;
}
return 0;
}
void createFood()// Random food
{
snake *food_1;
srand((unsigned)time(NULL));// To prevent the same random number being generated each time, the seed is set to time
food_1 = (snake*)malloc(sizeof(snake));
while ((food_1->x % 2) != 0) // Make sure it's an even number, so that the food can meet the snake head
{
food_1->x = rand() % 52 + 2;
}
food_1->y = rand() % 24 + 1;
q = head;
while (q->next == NULL)
{
if (q->x == food_1->x && q->y == food_1->y) // Determine if the body of the snake overlaps with the food
{
free(food_1);
createFood();
}
q = q->next;
}
Pos(food_1->x, food_1->y);
food = food_1;
printf(" s ");
}
void cantCrossWall()// Can't wear wall
{
if (head->x == 0 || head->x == 56 || head->y == 0 || head->y == 26)
{
endGamestatus = 1;
endGame();
}
}
void snakeMove()// Snakes' , on U, Under the D, On the left L, right R
{
snake * nexthead;
cantCrossWall();
nexthead = (snake*)malloc(sizeof(snake));
if (status == U)
{
nexthead->x = head->x;
nexthead->y = head->y - 1;
if (nexthead->x == food->x && nexthead->y == food->y)// If the 1 A food //
{
nexthead->next = head;
head = nexthead;
q = head;
while (q != NULL)
{
Pos(q->x, q->y);
printf(" s ");
q = q->next;
}
score = score + add;
createFood();
}
else // If there is no food //
{
nexthead->next = head;
head = nexthead;
q = head;
while (q->next->next != NULL)
{
Pos(q->x, q->y);
printf(" s ");
q = q->next;
}
Pos(q->next->x, q->next->y);
printf(" ");
free(q->next);
q->next = NULL;
}
}
if (status == D)
{
nexthead->x = head->x;
nexthead->y = head->y + 1;
if (nexthead->x == food->x && nexthead->y == food->y) // There is food
{
nexthead->next = head;
head = nexthead;
q = head;
while (q != NULL)
{
Pos(q->x, q->y);
printf(" s ");
q = q->next;
}
score = score + add;
createFood();
}
else // There is no food
{
nexthead->next = head;
head = nexthead;
q = head;
while (q->next->next != NULL)
{
Pos(q->x, q->y);
printf(" s ");
q = q->next;
}
Pos(q->next->x, q->next->y);
printf(" ");
free(q->next);
q->next = NULL;
}
}
if (status == L)
{
nexthead->x = head->x - 2;
nexthead->y = head->y;
if (nexthead->x == food->x && nexthead->y == food->y)// There is food
{
nexthead->next = head;
head = nexthead;
q = head;
while (q != NULL)
{
Pos(q->x, q->y);
printf(" s ");
q = q->next;
}
score = score + add;
createFood();
}
else // There is no food
{
nexthead->next = head;
head = nexthead;
q = head;
while (q->next->next != NULL)
{
Pos(q->x, q->y);
printf(" s ");
q = q->next;
}
Pos(q->next->x, q->next->y);
printf(" ");
free(q->next);
q->next = NULL;
}
}
if (status == R)
{
nexthead->x = head->x + 2;
nexthead->y = head->y;
if (nexthead->x == food->x && nexthead->y == food->y)// There is food
{
nexthead->next = head;
head = nexthead;
q = head;
while (q != NULL)
{
Pos(q->x, q->y);
printf(" s ");
q = q->next;
}
score = score + add;
createFood();
}
else // There is no food
{
nexthead->next = head;
head = nexthead;
q = head;
while (q->next->next != NULL)
{
Pos(q->x, q->y);
printf(" s ");
q = q->next;
}
Pos(q->next->x, q->next->y);
printf(" ");
free(q->next);
q->next = NULL;
}
}
if (biteSelf() == 1) // Judge if you're going to bite yourself
{
endGamestatus = 2;
endGame();
}
}
void pause()// suspended
{
while (1)
{
Sleep(300);
if (GetAsyncKeyState(VK_SPACE))
{
break;
}
}
}
void runGame()// Control of the game
{
Pos(64, 15);
printf(" You can't walk through walls. You can't bite yourself \n");
Pos(64, 16);
printf(" With write . left . please . → separately control the movement of the snake .");
Pos(64, 17);
printf("F1 To speed up, F2 To slow down \n");
Pos(64, 18);
printf("ESC : quit the game .space : pause the game .");
Pos(64, 20);
printf("C Language research centre www.clang.cc");
status = R;
while (1)
{
Pos(64, 10);
printf(" Score: %d ", score);
Pos(64, 11);
printf(" Score per food: %d points ", add);
if (GetAsyncKeyState(VK_UP) && status != D)
{
status = U;
}
else if (GetAsyncKeyState(VK_DOWN) && status != U)
{
status = D;
}
else if (GetAsyncKeyState(VK_LEFT) && status != R)
{
status = L;
}
else if (GetAsyncKeyState(VK_RIGHT) && status != L)
{
status = R;
}
else if (GetAsyncKeyState(VK_SPACE))
{
pause();
}
else if (GetAsyncKeyState(VK_ESCAPE))
{
endGamestatus = 3;
break;
}
else if (GetAsyncKeyState(VK_F1))
{
if (sleeptime >= 50)
{
sleeptime = sleeptime - 30;
add = add + 2;
if (sleeptime == 320)
{
add = 2;// To prevent to 1 And then we add it back again
}
}
}
else if (GetAsyncKeyState(VK_F2))
{
if (sleeptime<350)
{
sleeptime = sleeptime + 30;
add = add - 2;
if (sleeptime == 350)
{
add = 1; // Guaranteed minimum score 1
}
}
}
Sleep(sleeptime);
snakeMove();
}
}
void initGame()// Start interface
{
Pos(40, 12);
system("title C Language research centre www.clang.cc");
printf(" Welcome to the snake game! ");
Pos(40, 25);
printf(" C Language research centre www.clang.cc.\n");
system("pause");
system("cls");
Pos(25, 12);
printf(" With write . left . please . → separately control the movement of the snake, F1 To speed up, 2 To slow down \n");
Pos(25, 13);
printf(" The acceleration will result in higher scores. \n");
system("pause");
system("cls");
}
void endGame()// End of the game
{
system("cls");
Pos(24, 12);
if (endGamestatus == 1)
{
printf(" Sorry, you hit the wall. Game over .");
}
else if (endGamestatus == 2)
{
printf(" Sorry, you bit yourself. Game over .");
}
else if (endGamestatus == 3)
{
printf(" Your game is over. ");
}
Pos(24, 13);
printf(" Your score is %d\n", score);
while (getchar() != 'y')
{
printf("close?[y]");
}
exit(0);
}
void gameStart()// Game initialization
{
system("mode con cols=100 lines=30");
initGame();
creatMap();
initSnake();
createFood();
}
int main()
{
gameStart();
runGame();
endGame();
return 0;
}