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);
         ^