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);
         ^