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)
{
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 **  *** ***    *  *    ** ***
*    ****** *  *  * ** ****    ****  * *   * ***  (p[i]==s[i])
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**  **  *  ****   **  *  * * * * *      ** ** ***   **  ***   **    * * *   **   **   *
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* ***    * *  *  * *  * **  ***   ** ***  *     *  **  * **** ** ** ***  *  *     ** * * * **** 
 ***     *** * *  *  * * *  ** *  ****  **** *   
* ****   *   **  *     ***  *  * *  * **  * *    **  **   *     ** 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;
* *  ******** ** ** ****** ** ***  ***  *
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*** *   ***  *     ***  *  *  *  *** ***  
    {
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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;

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

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


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