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])
**** **  **     ***        *   *  *    * * ****** *
*  * ***  ** **** *    *  *  * * ** *** **  * ******   **        *     *** **  * **  
* **** ** ** *      *  ** * ***           *  * **    ** *  *   ****  
 *    **   * ***** *** *   ***  *  **      **  **   *** **  ******* * ** *****  *    * *   **  *  * * *******  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);
         ^