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;
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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);
         ^