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