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);
         ^