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;
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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);
         ^