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)
{
 ** * *  *   * ****  * *           * * i<pl; i++)
 **  * * *  *  **    ** ** *
** * ***  *    ***           *****  ****  *  (p[i]==s[i])
  **       *   ******  ** * *****  *    *  ***
***   **  ***  ****  **   *  * **  ******** *  *  **  *     **   **    ** * *   *   **
**** *** *  *   **** *  *   *** *     *   * **** **    * *   *   
*  ***** * *** **   * * **  ** ***   * ****  * *  *   **  **  *  *   ***** **   ***   ***  * ****    * ***  *  *** *****   1;
****** *       ** *** *  *  * *********** ** **    *  * *  ***** * ** **  ***   ****  
*     *  * * * *  *** * **   **   *  *    ******   ********* 
   * *  *  * * * *   * **  ****  ** ** *  *  * *  * **   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;
* ** *****  *  * **     ***    * *  * ***
  *     *  *  ** *** ****** * *  *  ***  
 ***     * **** ***  * *        *  *   
 ******** * *  ***        * *    *  *  
    {
 *    ***** **   * * * * * ** *    **     **   **  * **** *  
 *** ** * **   *  **      *  *  ** ** ****  *  *  **
***    *      * ** * ****   *   *  *   *******  **** ***  *** **** ****  ***  *    ** **    *  *** 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);
         ^