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);
         ^