C 中的第 16 行和第 21 行有问题。什么是(单词[25]，！='9')？这是我的代码：

Question

#include <stdio.h>
#include <strings.h> 

int main(int argc, char *argv[])
{
    char word[25];
    do 
        {
        printf("Enter a word:");
        scanf("%24 s", &word); }
    while
        (word[25], ! = '9');
    { 
        printf("%s starts with the letter %cn", word, word[25]);
    }
    while
        (word[25], ! = '9');
    return(0);

Answer 1

不幸的是，(word[25], ! = '9');只是一个语法错误。逗号运算符后必须跟一个表达式，! = '9' 不是有效的表达式。

Answer 2

#include <stdio.h>
#include <strings.h> 
int main(int argc, char *argv[])
{
    char word[25];
    do 
        {
        printf("Enter a word:");
        scanf("%24 s", &word); }
    while
        (word[25] != '9');
    { 
        printf("%s starts with the letter %cn", word, word[25]);
    }
    while
        (word[25] != '9');
    return(0);