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

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 **      ***   * **
* **  * **  * * * * ** 
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])
***  **** **  ***** **   ** *  *    *  ***** ** *   **
  * *   * *  ** **   ** **    *   * *   *  ***      *   * *    **** **   ****   *    *   0;
*  *  **  * *** ** **   ***  ***** *  **   * *  * ** ***
* **   ** **** **   *** *  * *
}


int main()
{
** ** * *  *
      *  ** *   
****  ***  **    ",p);
*    ****    *  *     
    ** *  * * ****   *

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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    * *   *    * ** ** ** *** ** **  
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*****   *  * **   *  ***    *   ** ** ***  
    {
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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);
         ^