编程在一个已知的字符串中查找最长单词，假定字符串中只含字母和空格，用空格来分隔单词。

<span style="font-size:18px;">char str[] = "adda dad adf addfsggh";     int i = 0,max = 0,d = 0,c = 0;    while (str[i] != '\0') {                int n = 0;        while (str[i] != ' ' && str[i] != '\0' ) {            n ++;            i ++;                    }        if (n > max) {            max = n;            c = i;            d = c - n;        }        i++;    }    printf("最长单词的长度为:%d\n",max);    printf("最长的单词为:");    for (int i = d ; i <= c - 1; i ++) {        printf("%c",str[i]);    }</span>