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