题解 | #配置文件恢复#

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
int main() {
    char input[21];
    char command[6][21] = {"reset", "reset board", "board add", "board delete", "reboot backplane", "backplane abort"};
    char exec[7][21] = {"reset what", "board fault", "where to add", "no board at all", "impossible", "install first", "unknown command"};
    while(fgets(input, sizeof(input), stdin) != NULL){
        int len = strlen(input);
        // printf("len is %d\n", len);
        if(input[len - 1] == '\n') input[len - 1] = '\0';
        len = strlen(input);
        // printf("len is %d\n", len);
        char firstword[21], secondword[21];
        int oneortwo = 1;
        int i = 0, j = 0;
        while(i < len) {
            // 读取第一个单词
            if(oneortwo == 1) {
                firstword[i] = input[i];
                i++;
                // 如果有空格证明有两个单词
                if(input[i] == ' ') {
                    firstword[i] = '\0';
                    i++;
                    oneortwo = 2;
                }
            } else if(oneortwo == 2) { 
                // 如果已经遇到过空格，读取第二个单词
                secondword[j++] = input[i++];
            }
        }
        secondword[j] = '\0';
        // printf("%s\n%s\n", firstword, secondword);
        // 如果只输入一字串
        int error = 0;
        if(oneortwo == 1) {
        // 只和一个关键字的命令行匹配。
            for(int x = 0; x < i; x++) {
                if(firstword[x] != command[0][x]){
                    // 如果输入一字串， 但是匹配命令有两个关键字，匹配失败
                    printf("%s\n", exec[6]);
                    error = 1;
                }
            }
            if(error == 0) {
                printf("%s\n", exec[0]);
            }
        } else if(oneortwo == 2){
        // 如果有两个词汇
        // 我们先检查第一个单词
            int notmatch[6] = {1};
            // 分别和每个命令匹配
            int firstwordlen = strlen(firstword);
            // printf("first word's length is %d\n", firstwordlen);
            for(int x = 1; x < 6; x++) {
                for(int y = 0; y < firstwordlen && command[x][y] != '\0'; y++) {
                    // printf("字母%c和%c\n",firstword[y],command[x][y]);
                    if(firstword[y] != command[x][y]) {
                        // 遇到不匹配的就标记不匹配
                        notmatch[x] = 1;
                        // printf("单词%s和%s不匹配\n",firstword,command[x]);
                        break;
                    }
                }
            }
        // 然后检查第二个单词
            char *secondwordToken;
            for(int x = 1; x < 6; x++) {
                if(notmatch[x] == 0) {
                    char *temp = (char *)malloc(sizeof(char) * 21);
                    // printf("the command is %s\n", command[x]);
                    int spaceindex;
                    for(int a = 0; a < strlen(command[x]); a++) {
                        if(command[x][a] == ' ') spaceindex = a;
                    }
                    strncpy(temp, command[x] + spaceindex + 1, strlen(command[x]) - spaceindex - 1);
                    secondwordToken = temp;
                    // printf("the command is %s\n", command[x]);
                    // printf("temp (seconde word) is %s\n", temp);
                    if(temp != NULL) {
                        for(int y = 0; y < j && secondword[y] != '\0'; y++) {
                            if(secondword[y] != temp[y]) {
                                notmatch[x] = 1;
                            }
                        }
                    }
                }
            }

            // 检查完两个单词之后如果notmatch里面只有一个0的话我们就找到要执行的命令了，如果有多个0或者没有0，则匹配失败
            int count = 0;
            int index = 0;
            for(int x = 1; x < 6; x++) {
                count += notmatch[x];
                if(notmatch[x] == 0) index = x;
            }
            if(count == 4) {
                printf("%s\n", exec[index]);
            }
            else {
                printf("%s\n", exec[6]);
            }
        }
    }
    return 0;
}