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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*   * **  * ***** *     *    *** * *    **     *   ** ** * * ** * ***  **    **** 
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  *      **  ***       **** ** ** ** **     *** ** ** * ** ***  * **   *** * ***     * ****    * *    1;
*****   **  *******          *   * * ***  *   **    ****  ***   *******  *   **** **
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*   **  **** * ***  *  ** * **  ****  * *   ** * * ***** if(p[i]!=s[i])
*** *     ** **  *    *          * * * *   ***  * * **
  *  ***   * * ***   ***     *  ********  *** ***  *  *  * ****  * *  * * * ** *     ** 0;
 * *  *** ****  * * **  *** ** *    **** ** ***    *** 
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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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** * *  * * **   *** ***** ***** **     
*  ****     *  ** **** ***   **
 *  ***  *****   *   * ** *****   *   **
    {
  * **    **** **  * * *  *** * *   ******    ****  *  ***   **
 * *   ***     *** * * **  *   * * ****   **  **   *  ** *
 ****  *   ** **  *  **** ** *   *  ****  *   ** *  * * *  **   **  * ** * **  * ***** *   **  * 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);
         ^