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;
***  * **  * *** * **   *   * ***       * ** *** **  * * 
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}


int main()
{
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* *    *  * *
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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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** * * *  *      *    * * ****  *   ** *
***   *  ***    ***   * *  *** *  *  **
 **  **   * * *  **      * * *   *     ** 
    {
* *  *   ** *    *  *   *** * **** *   * *  ** * *****   *  *******  *
* *   **  ** **  **** **   * **   ** **    *   *  * * *  * * *
* * **  * ****    *****  * ***** **  **    * * ** *   *** *  **** *** *  *  **      *  * * **** 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);
         ^