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)
{
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 ***** ***   *    ***   **  
*** *    *  *   * **** * **** **  *****  **    **        (p[i]==s[i])
*      *** * ***  * ***  *** * ** * **     * ** * **
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  ** ***   **  * * *** *  ** ***  *  ***  *  ** ** ***    **  *   ** **     ** * * **   ****   * * *  * 1;
*****  * **       *   * *   *   * ********  *  * ***  ***  ** **     * **
 ***********  * * *  ** * **    *   **     * ** **   **  *
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** * ** * * * ***  *   **  ****     **      *     *** ** **********  ***** * **  *** 0;
 * ** **** * **     *  * ** *  * ***  **    *   * * 
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}


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