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])
 **  **    **   * ** *  *  ** *    ** ***  *  *** 
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* ** * * ** * *   * *   ** * *** *  *  *****  *   ***   ** ******** * **** *** * * *  
* *** *  * *** * *       *  * * ***  * * * ** **  ***** ** *    *     * * *      **  *    * * ** *   * *  *  ** * * 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);
         ^