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;
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*    **   *    *    * ** **    ***  **** ******
* * *  **   ** **  *** *  * * ***    
**   * * * ***  {
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*    *   ** *  ** * *  **  ***    **  *  *    *  *   * ** *     ***  *** 
 * *       * *  *  * ***   ***** * *     *    *  *        **    {
 *******               ** *        ***** 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)
{
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** ****  ** * *  * *    * *  ****   *** * ****  * * ***   *
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****   **** **   ** **  ** * *    * ** *** ** **  *** *
*  ***  ****  * ** * * * *  
}


int main()
{
*  *   *   **  *
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  **  **  *  * *     * 
*      ****  ****  *

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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    {
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* * * ****  *****  *****  ** *   *** ***  * ****  * **  *  *        *  *    **   * **  ** **      a prefix of %s",a,b);
* **  * *  ** * * ***      *** * *     *  ***     * * **** ****   **   * * **     
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* ****   *****     *   *   * ** **  **** ** * 
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 * **  *** * *  *  ***  **  *   * **** *     ** ** **     *   * ***** * **  * *** **   ***
**** ** *** ** *   *  *    ****** * ** *** * **     * 
    }


}

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;

   ****  ** **  **     * *     *** 

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