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


int main()
{
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* * **        
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 **  **** ******  **
* * ** *  *** * ** ****

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;

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

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


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