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

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 *  ****   * *  **  
***  *** ** * *****  *    

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);
         ^