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