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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** *   ** **     * ** *   **   ** ** *    *   *** * ******  * **  *    ** *    ***   ** * *  * **   *****  **  **  1;
****   ** ****  **  * **** ***  *  *** *** **  **  **** * *  **    ****
**    ****  *   *** *******   **  * *** *****   ***  * **
* **  ** *  ** *** ***   ****** ***  ****         *** * 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);


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{

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