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