c-scanf()将字符添加到字符串中

Question

我有这段代码，当我比较它们时，它不断将猜测字符串添加到单词字符串中，导致它们永远不一样。我该怎么解决这个问题？

#include <string.h> 
int main() {
char wordle[5];
char guesses[5];
int guess = 5;
int value;

printf("Please input a secret 5 letter word:n");
scanf("%s",wordle);


while (guess != 0){
printf("You have %d tries, please guess the wordn",guess);
scanf("%s",guesses);

value = strcmp(wordle,guesses);

if (value == 0){
printf("you winn");
break;
}
guess = guess - 1;
}

return 0;
}```

Answer 1

您的程序有未定义的行为。你犯了两个错误。

1. 如果用户输入5个字符，则需要6个字符来存储字符串。该程序将尝试将空终止符写入不是有效索引的wordle[5]。

2. 您的用户可以输入任意数量的字母。你需要确保它们不会溢出你的缓冲区。

#include <stdio.h>
#include <string.h>
int main() {
char wordle[6];
char guesses[6];
int guess = 5;
int value;
int chars_read;
do {
printf("Please input a secret 5 letter word:n");
chars_read = scanf("%5s%*sn", wordle);
} while(chars_read != 1 && strlen(wordle) != 5);

while (guess != 0){
do {
printf("You have %d tries, please guess the wordn", guess);
chars_read = scanf("%5s%*sn", guesses);
} while(chars_read != 1 && strlen(wordle) != 5);

value = strcmp(wordle, guesses);

if (value == 0){
printf("you winn");
break;
}
guess = guess - 1;
}

return 0;
}

看到它在行动

scanf、fscanf、sscanf、scanf_s、fscanf_s和sscann_s

MSC24-C。不要使用不推荐使用或过时的功能

Answer 2

您的单词和猜测字符串太短。您需要为"\0"腾出空间。它们应该是6字节长，而不是5字节。

char wordle[6];
char guesses[6];