C language actual combat guessing game

Preface

The knowledge involved

1.switch Branch statement
2. The generation of random numbers and the change of seeds
3.do Loop statement
4. Pointer array

Game design

Basic design logic

In order to realize the guessing game , We simply design the following basic process .
1. Determine the gesture of the computer .
2. Show ” Rock-paper-scissors “ , Then the player inputs his own gesture .
3. Make a win or lose judgment , Show results .
4. Ask if you want to continue , If you want to continue, go back to 1 .

Let's explain how to complete each step one by one ：

Determine computer gestures

You can use random numbers to determine computer gestures

Show ” Rock-paper-scissors “, How can players input the gesture they want to make

Show gestures , We'd better use numbers instead of strings , Because strings are prone to input errors . To avoid this kind of mistake , We design stone scissors and cloth as numbers . Such as ： stone （0） scissors （1） cloth （2）

Judge , Show results

Let's set the variable human and comp To represent the gestures of players and computers respectively , Then according to the common expression （human - comp +3）% 3 To carry out , If the result is 0 It's a draw ,1 Is the computer victory ,2 Is the player wins

Whether or not to continue

We should use do sentence

Code display ：

#include<stdio.h>
#include<time.h>
#include<stdlib.h>
int main()
{
    
	int human; /* Player's gesture */
	int comp;/* Computer gestures */
	int judge;/* Judging the outcome */
	int retry;/* Do you want to do it again */
	srand(time(NULL));
	puts(" Start the game ！");
	do
	{
    
		comp = rand() % 3;/* Set the gesture of the computer to represent the range of numbers （0~2）*/
		printf("\a\n Rock-paper-scissors ··· stone （0）  scissors （1）  cloth （2）：");
		scanf("%d", &human);
		printf(" The computer is ：");
		switch (comp)
		{
    
		case 0:printf(" stone \n"); break;
		case 1:printf(" scissors \n"); break;
		case 2:printf(" cloth \n");   break;
		}
		judge = (human - comp + 3) % 3;
		switch (judge)
		{
    
		case 0:printf(" We are in a draw ！"); break;
		case 1:printf(" You lost ！"); break;
		case 2:printf(" You won ！"); break;
		}
		printf(" Do you want to do it again ？·· no （0） yes （1）");
		scanf("%d", &retry);
	} while (retry == 1);
	return 0;
}

Let's take a look at the specific operation results ：

The above code uses branch statements switch

How to better display gestures

The above code only shows the gestures of the computer , No player's gestures are displayed , Such a program is obviously not playable , Next, we will show the player's gestures according to the above idea .

Code display ：

#include<stdio.h>
#include<time.h>
#include<stdlib.h>
int main()
{
    
	int human; /* Player's gesture */
	int comp;/* Computer gestures */
	int judge;/* Judging the outcome */
	int retry;/* Do you want to do it again */
	srand(time(NULL));
	puts(" Start the game ！");
	do
	{
    
		comp = rand() % 3;/* Set the gesture of the computer to represent the range of numbers （0~2）*/
		do 
		{
    
			printf("\a\n Rock-paper-scissors ··· stone （0）  scissors （1）  cloth （2）：");
			scanf("%d", &human);
		} while (human < 0 || human>2);/* Display the player's input number , Prevent players from entering randomly */
		printf(" The program is ：");
		switch (comp)
		{
    
		case 0:printf(" stone \n"); break;
		case 1:printf(" scissors \n"); break;
		case 2:printf(" cloth \n");   break;
		}
		printf(" What the players bring out is ：");
		switch (human)
		{
    
		case 0:printf(" stone \n"); break;
		case 1:printf(" scissors \n"); break;
		case 2:printf(" cloth \n");   break;
		}
		judge = (human - comp + 3) % 3;
		switch (judge)
		{
    
		case 0:printf(" We are in a draw ！"); break;
		case 1:printf(" You lost ！"); break;
		case 2:printf(" You won ！"); break;
		}
		printf(" Do you want to do it again ？·· no （0） yes （1）");
		scanf("%d", &retry);
	} while (retry == 1);
	return 0;
}

Running results ：

Although the above code can solve the problem , But the string representing stone scissors and paper should exist as an array , Instead of writing it every time . Let's show the code first .

Code display ：

#include<stdio.h>
#include<time.h>
#include<stdlib.h>
int main()
{
    
	int i;
	int human; /* Player's gesture */
	int comp;/* Computer gestures */
	int judge;/* Judging the outcome */
	int retry;/* Do you want to do it again */
	const char *hd[] = {
     " stone "," scissors "," cloth " }; /* gesture */
	srand(time(NULL));
	puts(" Start the game ！");
	do
	{
    
		comp = rand() % 3;/* Set the gesture of the computer to represent the range of numbers （0~2）*/
		do
		{
    
			printf(" Rock-paper-scissors ···");
			for (i = 0; i < 3; i++)
			{
    
				printf("(%d) %s ", i, hd[i]);
			}
			printf(":");
			scanf("%d", &human);
		} while (human < 0 || human>2);
		printf(" Program out %s, Player out %s\n", hd[comp], hd[human]);
		judge = (human - comp + 3) % 3;
		switch (judge)
		{
    
		case 0:printf(" We are in a draw ！"); break;
		case 1:printf(" You lost ！"); break;
		case 2:printf(" You won ！"); break;
		}
		printf(" Do you want to do it again ？·· no （0） yes （1）");
		scanf("%d", &retry);
	} while (retry == 1);
	return 0;
}

We use an array of pointers to strings , The effect of this writing will be better than two-dimensional array
It is worth mentioning that if we write like this ：char *hd [ ]={“ stone ”,“ scissors ”,“ cloth ”} Some of our compilers will report errors , The reason is because ： character string “ Rock-paper-scissors ” Is a string constant , It needs to be saved in the global const Memory area , So we should write this way ：const char *hd [ ]={“ stone ”,“ scissors ”,“ cloth ”}

Increase the display of the number of wins and losses

With the increase of our functions , We will find that , The program is getting bigger , If all functions are required main Function to complete , Obviously a little too much , So we should use functions , Classify the corresponding functions , This will make the program easier to understand .

Let's take a look at the modified code ：

#include<stdio.h>
#include<time.h>
#include<stdlib.h>
int human;/* Player gestures */
int comp;/* Computer gestures */
int win_no;/* Number of victories */
int lose_no;/* Number of failures */
int draw_no;/* The number of draws */

const char* hd[] = {
     " stone "," scissors "," cloth " };

/*--- Initialization treatment ---*/
void initialize()
{
    
	win_no = 0;
	lose_no = 0;
	draw_no = 0;
	srand(time(NULL));/* Random number seed */
	printf(" The guessing game begins ！\n");
}
/*--- Read / Generate gestures ---*/
void jyanken()
{
    
	int i;
	comp = rand() % 3;/* Random number range */
	do
	{
    
		printf(" Rock-paper-scissors ···");
		for (i = 0; i < 3; i++)
		{
    
			printf("(%d) %s ", i, hd[i]);
		}
		printf(":");
		scanf("%d", &human);/* Read player gestures */
	} while (human < 0 || human>2);
}
/*--- Update failed / victory / The number of draws ---*/
void count_no(int result)
{
    
	switch ( result)
	{
    
	case 0:draw_no++; break;
	case 1:lose_no++; break;
	case 2:win_no++; break;
	}
}
/*--- Display the judgment result ---*/
void disp_result(int result)
{
    
	switch (result)
	{
    
	case 0:puts(" It ends in a draw ！"); break;
	case 1:puts(" You failed ！"); break;
	case 2:puts(" You won ！"); break;
	}
}
/*--- Whether to continue the game ---*/
int confirm_retry()
{
    
	int x;
	printf(" Do you want to do it again ？··· no （0） yes （1）");
	scanf("%d", &x);
	return x;
}


int main()
{
    
	int judge = 0;
	int retry = 0;
	initialize();
	do
	{
    
		jyanken();
		printf(" Program out %s, Player out %s\n", hd[comp], hd[human]);
		judge = (human - comp + 3) % 3;
		count_no(judge);
		disp_result(judge);
		retry = confirm_retry();

	} while (retry == 1);
	printf("%d - %d negative %d flat .\n", win_no, lose_no, draw_no);
	return 0;
}

Operation result display ：

So we can write different functions , Will be originally bloated main Functions become easy to understand .

Perfect version of guessing game

In order to make the guessing game more perfect , We have added the function of automatically ending the game by winning three times , In this way, there is no need to ask the player whether to continue .
Add this function , Can better show , We divide the function of a large program into a single function , It is a great help for the later code addition and modification . The smaller functions that divide the functions of large programs , The more times this function can be reused , It will be more convenient for maintaining stability in the later stage ！
Code display ：

#include<stdio.h>
#include<time.h>
#include<stdlib.h>
int human;/* Player gestures */
int comp;/* Computer gestures */
int win_no;/* Number of victories */
int lose_no;/* Number of failures */
int draw_no;/* The number of draws */

const char* hd[] = {
     " stone "," scissors "," cloth " };

/*--- Initialization treatment ---*/
void initialize()
{
    
	win_no = 0;
	lose_no = 0;
	draw_no = 0;
	srand(time(NULL));/* Random number seed */
	printf(" The guessing game begins ！\n");
}
/*--- Read / Generate gestures ---*/
void jyanken()
{
    
	int i;
	comp = rand() % 3;/* Random number range */
	do
	{
    
		printf(" Rock-paper-scissors ···");
		for (i = 0; i < 3; i++)
		{
    
			printf("(%d) %s ", i, hd[i]);
		}
		printf(":");
		scanf("%d", &human);/* Read player gestures */
	} while (human < 0 || human>2);
}
/*--- Update failed / victory / The number of draws ---*/
void count_no(int result)
{
    
	switch ( result)
	{
    
	case 0:draw_no++; break;
	case 1:lose_no++; break;
	case 2:win_no++; break;
	}
}
/*--- Display the judgment result ---*/
void disp_result(int result)
{
    
	switch (result)
	{
    
	case 0:puts(" It ends in a draw ！"); break;
	case 1:puts(" You failed ！"); break;
	case 2:puts(" You won ！"); break;
	}
}
/*--- Whether to continue the game ---*/
int confirm_retry()
{
    
	int x;
	printf(" Do you want to do it again ？··· no （0） yes （1）");
	scanf("%d", &x);
	return x;
}


int main()
{
    
	int judge = 0;
	int retry = 0;
	initialize();
	do
	{
    
		jyanken();
		printf(" Program out %s, Player out %s\n", hd[comp], hd[human]);
		judge = (human - comp + 3) % 3;
		count_no(judge);
		disp_result(judge);
		retry = confirm_retry();

	} while (win_no < 3 && lose_no < 3);
	printf(win_no == 3 ? "\n You won ！\n" : "\n I won ！\n");
	printf("%d - %d negative %d flat .\n", win_no, lose_no, draw_no);
	return 0;
}

We didn't even rewrite more than three lines of code , But we have added a new function . The reason is that the function we split above is sufficiently detailed , Therefore, we only need to add main Modify the final judgment in the function .

summary

Game code

#include<stdio.h>
#include<time.h>
#include<stdlib.h>
int human;/* Player gestures */
int comp;/* Computer gestures */
int win_no;/* Number of victories */
int lose_no;/* Number of failures */
int draw_no;/* The number of draws */

const char* hd[] = {
     " stone "," scissors "," cloth " };

/*--- Initialization treatment ---*/
void initialize()
{
    
	win_no = 0;
	lose_no = 0;
	draw_no = 0;
	srand(time(NULL));/* Random number seed */
	printf(" The guessing game begins ！\n");
}
/*--- Read / Generate gestures ---*/
void jyanken()
{
    
	int i;
	comp = rand() % 3;/* Random number range */
	do
	{
    
		printf(" Rock-paper-scissors ···");
		for (i = 0; i < 3; i++)
		{
    
			printf("(%d) %s ", i, hd[i]);
		}
		printf(":");
		scanf("%d", &human);/* Read player gestures */
	} while (human < 0 || human>2);
}
/*--- Update failed / victory / The number of draws ---*/
void count_no(int result)
{
    
	switch ( result)
	{
    
	case 0:draw_no++; break;
	case 1:lose_no++; break;
	case 2:win_no++; break;
	}
}
/*--- Display the judgment result ---*/
void disp_result(int result)
{
    
	switch (result)
	{
    
	case 0:puts(" It ends in a draw ！"); break;
	case 1:puts(" You failed ！"); break;
	case 2:puts(" You won ！"); break;
	}
}
/*--- Whether to continue the game ---*/
int confirm_retry()
{
    
	int x;
	printf(" Do you want to do it again ？··· no （0） yes （1）");
	scanf("%d", &x);
	return x;
}


int main()
{
    
	int judge = 0;
	int retry = 0;
	initialize();
	do
	{
    
		jyanken();
		printf(" Program out %s, Player out %s\n", hd[comp], hd[human]);
		judge = (human - comp + 3) % 3;
		count_no(judge);
		disp_result(judge);
		retry = confirm_retry();

	} while (win_no < 3 && lose_no < 3);
	printf(win_no == 3 ? "\n You won ！\n" : "\n I won ！\n");
	printf("%d - %d negative %d flat .\n", win_no, lose_no, draw_no);
	return 0;
}

Knowledge summary

Branch statement

if Statement and switch Statements are all branch statements , But if a single expression is used to branch the program , here switch Sentences are obviously better than if sentence .

Pointer array

in the majority of cases , Use an array of pointers to strings to implement a collection of strings of different lengths , It's more convenient than using a two-dimensional array .

character string “xxx” Is a string constant , It needs to be saved in the global const Memory area , So we should write this way ：const char *hd [ ].

Scope

Identifiers are the names of variables and functions , Its general scope is scope .
In block { } Identifier declared in , Is valid within the block , It is invalid outside the block . Once the variables in the block are invalid outside the block , This kind of variable is also called local variable .

Function segmentation

When a program has enough functions , When complex enough , We should divide the function of each small block into a function , This will facilitate later maintenance and add new functions . And the less function a function has , Then it can be used in a wider range ！