Final Exam 2 (20%)

Question

A string p is a prefix of a string s if the leading characters of s are identical to p. For example, "abc" is a prefix of "abcde". Develop a function prefix that checks if a C string p is a prefix of another C string s.

p是s的前綴若s開頭的一段字串等於p。例如，"abc"是"abcde"的前綴。寫一個程式 判斷字串p是否字串s的前綴。

Example input 1:

abc
abcde

Example output 1:

abc is a prefix of abcde

 

Example input 2:

bc
abcde

Example output 2:

bc is not a prefix of abcde

 

Answer 1

Hidden content!
 **  * ***   * * *** *
*   *   *** *  * *     

int main()
{
     ***   ******  char **** * 
  * *      * * int i,c=0;
*  ***** *** *    *****    * * *  * *   *   **  ** **
*   *     *  ***   *     *** *  * **      ******
******     * **    ***** *** *  *  *      *
*  * *     *     {
* **  *      *  ***    ****    *  
 * **  *  ** ** **   * ****  * {
   **  * * *    *   ***       ** **  *** **  *  ** * **** ***** *  ****** 
***** * **   *     *** * * ***    ** *   * * * ***    ** *  {
** ****                     * ***   * c=0;
 *  ** *   *  *  **  ** * *  * ** *    * ** * *  * * *   }
 *  * *  *  * *      **         **    **  *** **  else *    ** ****** *    * *** *    *
  *** **   *  *   **  *  *    ** *  *  *  * **    *****   * *  * {
  **  **   ** **   *      **** * *  *   ** ** * ** *   **  * *  ****       c++;
* *  *      ** * *  *  *** *   ** ***   * * * * *  * *         *   }
**  ***  * *   ****** *     *  }
**   **  *** * 
** **    *  **** if(c==0)
  ***** ** * ***   **        *    * **** * ** **  is not a prefix of **  * *** * 
 ** *  ***     else
*** * **  *   ** * *     *  **** **    ** is a prefix of * *  *  * 
** * * ******  }
 *  *   * ** * return 0;
}

Comments

prog.c: In function 'main':
prog.c:8:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&a);
           ^
prog.c:9:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&b);
           ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

prog.c: In function 'main':
prog.c:10:6: warning: implicit declaration of function 'stlen' [-Wimplicit-function-declaration]
   if(stlen(b)>strlen(a))
      ^~~~~
/tmp/ccnE3ufV.o: In function `main':
prog.c:(.text+0x5b): undefined reference to `stlen'
collect2: error: ld returned 1 exit status

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Correct output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 2

Hidden content!
**  **  ** ** ** ***    
   *   *******  **** *   * 
int main()
{
**  ******    * ap;
*****        *** **** **     ** * **    * *  ** || ap=a)
 *  ** * *** * *  *  ** *   *   *  ** **   is a prefix of abcde\n");
** ***    ** *  
** **  ***  
******* *** *** *** **  *           * *  *  *** is not a prefix of abcde");
* ******      **      **    ** * *   *    ** ***   * ** * *  **  *  * *   ** 0;
             **   *     * **  ***  * *** **  ***    ***      * *  * ***
  

Comments

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

Answer 3

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*  ****   ****   

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
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* *  *** *****  *      * 
*    *      **  *  * * ** * ***** *   **  *   * *    ** *    (p[i]==s[i])
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*** *** *** ***** ** ****  ***** ** *   *** **    ********     *    ** *   *** * * *  *
*   * **    ***  *   * *      * * * * *  ** **  *  * *********  *  *** **  **   * **** **  * * *   **   ** *  **** * ** 1;
*** *** *  * * * * *       *** **  * *  ***  ***  * * * ***  **  *******   **    *
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   ** **     ******   *    *  *****    **  *  *  *   **  if(p[i]!=s[i])
********  ***** *      ** ***  * ****       *     *  * 
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}


int main()
{
* *  ***    
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  ** *  *     * * **   
*** ** *  ** **  ** * 

sl=strlen(s);
pl=strlen(p);


****  **       && pl<sl)
{

*      * * ** *    *** ** *    *** * is a prefix of %s",p,s);
}else
{
printf("%s is not a prefix of %s",p,s);
}





}

Comments

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 4

Hidden content!
#include<stdio.h>
#include<string.h>
int main()
{
 *  ** *  * *   *   ***    **** a[99],b[99];
    int l,i;
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  ** ****     * * ** * *  * *   **  ** * *
    {
 ** *  *      *    **    ** *  ** **** ***** *  * **  ** *
 ***** ****    **  * *   * *** ** ***   ****    *  *** * 
    *   * ***** * **** * ** ***  *   * ***   ***** *   ** **    * *** *** ** * **          * * ** ** a prefix of %s",a,b);
 * **     *  ***     *   * ** **  * ** ** **  *    *        ** *   *  * ****    ** *
** *  *   ***    ** * * * * **** ** *  **     ***   
***  *   * *  * *  *    * * ****    * *   *     ** **  ****
*  *   *  * **   ********** *** **  **** * ********    *
  **** *  **** **** **    *  *** **** *  *  * ******* *  *    ** *  * **  * *     ** *  ** not a prefix of %s",a,b);
 *  ******** **  ** ** ****   ** *** ** *   ** * *** *   *  *  *  *** *    *  ** * * *   
*     *  **********   *** * *  ** **  ***** * **   **  *
    }


}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 5

Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

int prefix(char a[100],char b[100]);


int prefix(char a[100],char b[100])
{
   *  * **  ** **   *  **  ** * * i;
 ***          * **     * **   count=0;
** **  * * * ***  ***** * ** *  len;

*  *  *  *  ** *     *  **     * **

 * *  *   * **  ****  * *  *  ** *** 
 ** *  *    * * * *  *   * 
***   * ****** *     ***** **    *  ***   ** **  *  ** **  *  *  *****
* ********  **      *  ****  ***   *   * * ***    * *** 
 *   *   *   * ** * ****  **  * *  *   *******  *** ** ***    * * *    *     **
      ** * *  **  ***  *    *** **** *** ***** *  *  * 
* ** * ****  *     **  ** **


*  * *** * *** ** ***    *  ****    ** 
    * * * *  *  *   *  * 
*** ****** *  ***   *  ***   ***   *** **   * *  * ****  1;
 *  *        * * *     **
   *  * **  **  *  *  ** ***  

   return 0;
}


int main()
{
****  ** ***  ** **    *  a[100];
 * *** ***** ****     * ****** b[100];


* *  **** * *  ** *** * *   * ** **  *  ***   **   * *
 * *  *   * * ** *      ** **  **** * *  * **    * * *   **** *

    *** * * * *** ** * *          ** 
        ** ***** **  ** ******  * ***   * 

 *** *** * * ** **    ** *    ** *** *

 {
 * ****   * * ** * ** **** * * * *  * *  *** * * *     ** **  *  **     is a prefix of %s",a,b);
***  * *  ***    ** **  *  **
***  *   ***   ******   *  **  * 
** *    **  **  * * 
  ** * *** * * ***  ** ** *  * *** *  *   * *  ** *  * ***  ** ***    ** is not a prefix of %s",a,b);
**  ** * * *** *  *** * **


 ***    *** **  *     *  * * **   0;
}

Comments

prog.c: In function 'main':
prog.c:45:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&a);
               ^
prog.c:45:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&a);
                    ^
prog.c:46:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&b);
               ^
prog.c:46:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&b);
                    ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 6

Hidden content!
 * * ***  ******  **
* ***      *     ** **** 

int *  
{
*   **** ********** ** *     **  * *     no idea, I *   *  even do it in the   *   ***  *** **
 * **** *    **  * * ***     *     * 0;
}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 7

Hidden content!
#include      **  *    ***
#include * * * **  * * *
#include  ***** ***   * *

int pref(char[],char[]);

int main(){

**    **   ****  * ** * **  *  * p[10],s[10];
 *** * **** * ** *  **  *** *  num;

  ** ****    * *   * **  *     ** ***
****  *  ***   * * * *  *** ** 
 * * * * * ***** *   * * * ** * ********** *    ***** * *   ****
   * ****   ** *** ** *     *  ** **      ** *** *   

 ** * *  * *    **  ** *  * * = pref(p,s);

****  * **** **   ***    **** *  *
  **  *  ** *  * **** ***  ** * * ***** * *     * ** * *     is a prefix of %s",p,s);
 ** **** *  ****   * *** * * ***   ** *
* **  ** *********   * ****  *  *    ** **** *   *  **  ***    is not a prefix of %s",p,s);


 return 0;
}

int pref(char p[30],char s[30]){
**** *  * *****  * *        i;

* **** *  ******  ***  ** ** * * ** *  *
 ** * ** ***** * * ****  **    * *  ** **        **  **       *** ******     **  ***   **  ** * *  **  **** *
  * * ** *  ***  ** **          *  *  ** **  *** ****   * ***     *** *     *   * **   *      *   ****  ** is a prefix of %s",p,s);
  ** **  * **  ** **** * * * *     **  * ***    **** *   
 ** *** **  *          *  **    * ***   ** * **  ***  *  *    * ** * ** *** *  *  **     **   **   is not a prefix of %s",p,s);

*   **  ** *  **  * *   ***

}

Comments

prog.c: In function 'main':
prog.c:12:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:13:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/tmp/cc0tBG5r.o: In function `main':
prog.c:(.text+0x1f): warning: the `gets' function is dangerous and should not be used.

---

prog.c: In function 'main':
prog.c:10:13: error: stray '#' in program
     int num;#include <stdio.h>
             ^
prog.c:10:14: error: 'include' undeclared (first use in this function)
     int num;#include <stdio.h>
              ^~~~~~~
prog.c:10:14: note: each undeclared identifier is reported only once for each function it appears in
prog.c:10:23: error: 'stdio' undeclared (first use in this function)
     int num;#include <stdio.h>
                       ^~~~~
prog.c:14:1: error: expected expression before 'int'
 int pref(char[],char[]);
 ^~~
prog.c: In function 'main':
prog.c:23:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:24:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^
prog.c: In function 'main':
prog.c:51:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:52:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~

---

prog.c: In function 'main':
prog.c:14:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:15:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^

Answer 8

Hidden content!
**** ****   *     ** *** **
*  *** * **  ** **  

int main()
{
 * ***** length1, *   c;
**  * ***   a[100];
     **   *  b[100];
** *** *  *  d[100];

***  *    **     ** *** * *** *    **  
**** *     * *   *  ** *    *  *** *

* **   **** ****  *   

*  * * *      *     **

*  *  *      * *
*****
 ** *   ** ** **  *  *** * is a prefix of *  ****   
* * * 
 **** *  ****  
**   **  
 **   * * ****  ** is not a prefix of  **** *
**** ** 

}

Comments

prog.c: In function 'main':
prog.c:11:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&a);
          ^
prog.c:12:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&b);
          ^
prog.c:24:11: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
           ^
prog.c:24:33: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
                                 ^

Answer 9

Hidden content!
**   ****   ** * * *  
*** **** **  *   * ** * *

int main()
{
***  * *   *  *      **     *   * * str;
 ** *  * * * * * *    ** *   *  i, p, s;

** *** ** *  * ***  *** ***  ***  * *** *   *** &p, &s);

**  *   ** * **  * **   **** (i<=0; &p; i++);
 *  * **  **** * *  ***  * * 
     * * ** *****  * **    **   ** ** ** **  ***   &p);
** * *     *  * *      ***   ***  *   **   ****** *
 ** * *  *** ***** **   
 *  *    ***    ***    *  

  **   *** ** * ** *****  * ** 0;
}

Comments

prog.c: In function 'main':
prog.c:12:7: error: expected '(' before '{' token
     if{}
       ^
prog.c:13:12: warning: too many arguments for format [-Wformat-extra-args]
     printf("abc", &p);
            ^~~~~
prog.c:14:13: warning: format '%d' expects a matching 'int *' argument [-Wformat=]
     scanf("%d");
             ^

Answer 10

Hidden content!
*     ** ** *** ***   *
* **      *  * *   ** *
int main (){
char *   * *
char    *   *
 *   ** **   *  * *  *  *** * ** 
*  ** **  * * **  * **  **** * ****  * *
*** * *** ****** * *   *****
*   * ****   *****   ** * *
*  * *** *  * ***  * *  
*  **   * *  is a prefix of * **  *  ******** 
}
else{
***** ***  * is not a prefix of %s  *** * *  **  * ***    *
}
* **  0;
}

Comments

prog.c: In function 'main':
prog.c:7:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string1);
         ^
prog.c:9:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string2);
         ^