为什么它不输入一些 else-if 语句是有原因的？

Question

一些 else-if 语句不像 'else if(strcmp(player1,player2) == 0) ' 或 'else if(strcmp(player1, "scissors") == 0)'。会不会是他们后来的'if'声明？它们是另一个有效的 else if 语句的副本（经过一些修改）。它们几乎相同，所以我不明白为什么它们不起作用。

#include <stdio.h>
#include <string.h>

int main(void) {
    
    char player1[25];
    char player2[25];
    
    while(1){
        
        printf("please type one of the following: rock, paper or scissors. Player1 goes first\n");
        scanf("%24s%24s",player1,player2);
        
        if (strcmp(player1, "rock") == 0)
        {
            if (strcmp(player2, "scissors") == 0)
                printf("player 1 wins, rock crushes scissors\n");
        }
        
        else if(strcmp(player1, "rock") == 0)
        {
            if (strcmp(player2, "paper") == 0)
                printf("player 2 wins, paper covers rock\n");
        }

        
        
        else if(strcmp(player1, "scissors") == 0)
        {
            if(strcmp(player2, "paper") == 0)
                printf("player 1 wins, scissor cuts paper\n");
        }
        
        else if(strcmp(player1, "scissors") == 0)
        {
            if(strcmp(player2, "rock") == 0)
                printf("player 2 wins, rock crushes scissors\n");
        }

        
        else if(strcmp(player1, "paper") == 0)
        {
            if(strcmp(player2, "rock") == 0)
                printf("player 1 wins, paper covers rock\n");
        }
        
        else if(strcmp(player1, "paper") == 0)
        {
            if(strcmp(player2, "scissors") == 0)
                printf("player 2 wins, scissor cuts paper\n");
        }

        
        

        else if(strcmp(player2, "rock") == 0)
        {
            if (strcmp(player1, "scissors") == 0)
                printf("player 2 wins, rock crushes scissors\n");
        }
        
        else if(strcmp(player2, "rock") == 0)
        {
            if (strcmp(player1, "paper") == 0)
                printf("player 1 wins, paper covers rock\n");
        }

        
        else if(strcmp(player2, "scissors") == 0)
        {
            if(strcmp(player1, "paper") == 0)
                printf("player 2 wins, scissor cuts paper\n");
        }
        
        else if(strcmp(player2, "scissors") == 0)
        {
            if(strcmp(player1, "rock") == 0)
                printf("player 1 wins, rock crushes scissors\n");
        }

        
        else if(strcmp(player2, "paper") == 0)
        {
            if(strcmp(player1, "rock") == 0)
                printf("player 2 wins, paper covers rock\n");
        }
        
        else if(strcmp(player2, "paper") == 0)
        {
            if(strcmp(player1, "scissors") == 0)
                printf("player 1 wins, scissor cuts paper\n");
        }

        
        else if(strcmp(player1,player2) == 0)
        {
            printf("nobody wins, let’s sing it again!\n");
        }
        else
            printf("incorrect input, try again\n");
    }

        return 0;
}

Answer 1

您的 if-else 语句没有意义。例如考虑这些 if-else 语句

    else if(strcmp(player1, "scissors") == 0)
    {
        if(strcmp(player2, "paper") == 0)
            printf("player 1 wins, scissor cuts paper\n");
    }
    
    else if(strcmp(player1, "scissors") == 0)
    {
        if(strcmp(player2, "rock") == 0)
            printf("player 2 wins, rock crushes scissors\n");
    }

两个 else if 语句具有相同的条件

    else if(strcmp(player1, "scissors") == 0)
    //...
    else if(strcmp(player1, "scissors") == 0)

所以第二个 else if 语句要么不会被执行，要么它的条件永远不会等于 true。

例如，您可以按以下方式编写单独的 if 语句

    if (strcmp(player1, "rock") == 0)
    {
        if (strcmp(player2, "scissors") == 0)
            printf("player 1 wins, rock crushes scissors\n");
        else if (strcmp(player2, "paper") == 0)
            printf("player 2 wins, paper covers rock\n");
    }
    else if(strcmp(player1, "scissors") == 0)
    {
        if(strcmp(player2, "paper") == 0)
            printf("player 1 wins, scissor cuts paper\n");
        else if(strcmp(player2, "rock") == 0)
            printf("player 2 wins, rock crushes scissors\n");
    }
    //...

为什么它不输入一些 else-if 语句是有原因的？

Is there a reason for why it doesn't enter some of the else-if statements?

c

if-statement

c-strings

strcmp