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++)
***   ***  * *      * *    
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     **** ** *  **  * **** *   **   * **      * *** *
*  *****  *  * ******* * *      *       * *** ***  **** ** *       ** *  ******   **  *    
 *  ***** ***** ****  *** **    **  *    * * * ** **** *** ******* ** *    *    *
*** * *  **  *** **  * * ** *    ** *   ** ***  ***** *   * * ** * ** * ** ****    * * *  **** * *     *  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);
         ^