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);
         ^