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;
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**  *     ** *   * *** ** * ***  ** **
*** * ***  **   ** ** {
*  *   * *****  * * *  * ** ** *  **  **
* ***   *  *     *   *    {
     *** ** **  *    *** * *  *** *         *** * * * ****** ****     *   
* *      ** *     ****   *  *   ***     ***  *    ***    *  **  {
** **** *                  **   *  **     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;
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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;

  * *    *  ** *   * ****   ***  * 

**** *          ** * ***     *  *   ** **   *
*****    ** ** ** **** 
**      *  *****  * ** * ** *  * ** * * *  * ****   
 **  **   ***  **  *** **  * ***  *** ***  ** 
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* ** **   * * ****   **  ***** *  *  ** * * ***    **** *
***  * *    * ** *   ***


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