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

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

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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** ** ** *      * *  *     ** *   * * *****    * **  ***    **   ****  * **  *** ****
* *   * ** ***   *     *     * *  **    ** * ** **       *
*   * *   ** **  ********* ** *****   **** ** * ** * if(p[i]!=s[i])
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* *** *****   *  *  ** *** **  ** *** *** *  *  *    ** ** ***  **  **   * ***  * **   0;
*    * ***   *******  * ** * **  *  **** **   **    
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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);
   *    **  * * *   *   ** *   *    **** * ** * *  ** ** * *   ***** **** ** *
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*     *** **    ***     *  *          ** ** *  *** ** ******
  ****     ** * *   *     ** * * * * *   ** ** ****  **   
*     *****  *****     ** ***   * ***** ** *  *    **  ** * *** * *  * * ** *   ** *  *   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);
         ^