c - 在 C 中测试等值图 - Argv 到字符数组

Question

我正在尝试创建一个简单的命令行测试是/不是等值线图(一个单词中没有重复的字母)，但我在使用 argv 作为字符数组时遇到了问题。

我做了一些搜索，这个答案使用了 strcopy , 然后给我一个更详细的 malloc answer .可能是因为我糟糕的 google-foo 我找不到循环遍历 argv 字符的示例。我试过的这段代码正在对字符串进行切片？:

 /* first argument is the number of command line arguments,
  * list of command line arguments, argv[0] == function name
  */
 int main(int argc, char *argv[]) {
     if(argc != 2){
         printf("error, bad arguments!\n");
         return 1;

     } else {
         char* isogram = NULL;
         isogram = (char*)malloc(sizeof(argv[1])+1);
         strcpy(isogram, argv[1]);

         for(int i=0; i<strlen(isogram); i++){
             printf("isogram[%d]==%s\n", i, &isogram[i]);
         }

         // detect_isogram(isogram);

     }

     return 0;
 }

输出:

gcc -o isogram isogram.c -std=c99; ./isogram testing
isogram[0]==testing
isogram[1]==esting
isogram[2]==sting
isogram[3]==ting
isogram[4]==ing
isogram[5]==ng
isogram[6]==g

注意:我尝试了 char *isogram[]=NULL 以为这是我想要初始化的，但正如网站所建议的那样，这只适用于 char *isogram = NULL.

编辑:我知道如何测试它们，只是无法让每个角色相互比较。每个索引返回 slice[i:]...

 for(int i=0; i<strlen(argv[1]); i++){
     for(int j=i+1; j<strlen(argv[1]); j++){
         printf("isogram[%d]==%s\n", i, &argv[1][i]);
         printf("isogram[%d]==%s\n", j, &argv[1][j]);
     }
 }

Answer 1

您不需要任何argv[1] 处理。您只需要将它传递给检测功能即可。

code00.c:

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


int detect_isogram(const char *word) {
    size_t len = strlen(word), i = 0, j = 0;
    for (i = 0; i + 1 < len; i++)
        for (j = i + 1; j < len; j++)
            if (word[i] == word[j])
                return 0;
    return 1;
}

int detect_isogram2(const char *word) {
    size_t len = strlen(word), i = 0;
    for (i = 0; i + 1 < len; i++)
        if (strchr(word + i + 1, word[i]))
            return 0;
    return 1;
}

int main(int argc, char *argv[]) {
    if (argc != 2) {
        printf("error, bad arguments!\n");
        return 1;
    } else {
        printf("detect_isogram returned: %d\ndetect_isogram2 returned: %d\n", detect_isogram(argv[1]), detect_isogram2(argv[1]));
        return 0;
    }
}

注意事项:

• 该算法很简单:对于字符串中的每个字符(从第 1 个^st 开始，但 不包括最后一个)，检查它是否在剩余部分字符串
  • 支票可以是:
    • 手动(遍历字符串的剩余部分(从搜索到的紧接的字符开始)，并比较字符)- detect_isogram
    • 通过 [CPPReference]: strchr - detect_isogram2

输出:

root@testserver:/home/cfati/work/so/q048873942# gcc code.c -o isogram
root@testserver:/home/cfati/work/so/q048873942# ./isogram testing
detect_isogram returned: 0
detect_isogram2 returned: 0
root@testserver:/home/cfati/work/so/q048873942# ./isogram ""
detect_isogram returned: 1
detect_isogram2 returned: 1
root@testserver:/home/cfati/work/so/q048873942# ./isogram 1
detect_isogram returned: 1
detect_isogram2 returned: 1
root@testserver:/home/cfati/work/so/q048873942# ./isogram 12345678
detect_isogram returned: 1
detect_isogram2 returned: 1
root@testserver:/home/cfati/work/so/q048873942# ./isogram 123456781
detect_isogram returned: 0
detect_isogram2 returned: 0
root@testserver:/home/cfati/work/so/q048873942# ./isogram qq
detect_isogram returned: 0
detect_isogram2 returned: 0

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更新#0

• 采纳了@chux的改进建议