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)
{
   * *   *** * **     * **  *   i<pl; i++)
*  * * * **  *      * 
  * **** **  **** *****   **  * * **** **  ***  **   (p[i]==s[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);
         ^