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);
         ^