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)
{
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   *****   **  *  ** *  *** ** *
** *  * * *******    *   * *  * * **** *  *  *    ***** (p[i]==s[i])
*   *  ** * * **** ****    *  *     **   ****  
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*  * * ** ** ****    ***    ***  ** *   *  * *    *  *   ** ****  * **  *  *  *  *   *  ***  ***  ** ***********   * 1;
*            *   * ****     **** * *  *  *  *  **** *  * * ******** * *  ***  
   * *** *    * * * ** ** **  * * *  **     ****  * 
 ***     *    *   **** * *        * * *  * ****  ****      ** if(p[i]!=s[i])
 ** *  *** * * *   *       * *****   **  * * *  ** * 
**  *             * *****         **  ** *  *  *   *  *          ****  *  * ** ** ** * *      0;
**** *** *  *** *  **  ** * *    **  **** * *****  ** *  *  
   * * *****  **    *  *  ** * * * 
}


int main()
{
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* **  **** * *  ",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);
         ^