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++)
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*    ** * * ** *** ******    ***** * ***     **     *****
* *   * *   *** ** *  * *  *  ****  *    ** * * *  *  **    **  ********  * *   
** * **   ***********  **     ** * ***  ****  *   *   * * *****  **** *****   **** * * 
****  *  *  * *** * **   *  *   * ** * *** * **   *   * * * *  *** *   *  *** * **    *  *  *    *  ***  * *  *  * *  1;
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****   * *         *    ** * * ** *** ***  *    ** ** 
 **** *   ** ** **** *  *** *  * *  ***  ****     * * * * 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);
         ^