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;
*** ** **** * *      * ***  * **  ***** 
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* * *    ******  {
 *       * ***   ** *  *******   *  *
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 ****    *** *  *****  *  *   ** **   * ** ** * * ** *   * **  
* **    *   ** *    **    *  **  ***       * **  ** *  **** * * * {
**  *  *               ** ** *    ***   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

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** * *  *   * *
*** * *  * *****  *
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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**  * *     * * *      
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*   **  ***   ** **   * **      *    ** ** **  **  ***
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*     ** * *   *  **         ** 
}


int main()
{
***  **  *** *  ****
* **  ** ***** *  *
*   * *   *  ",p);
*  **        * *    
*  * * ********   **  **

sl=strlen(s);
pl=strlen(p);


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{

 *  *    ***  *  *  * *  ** ** **   *   * * 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()
{
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    int l,i;
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*  **     * * ** *   ***    * ***
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    {
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*  *  ** ** ****    ***  * *   ** **** *     * ***       *  *  ***     ** * **   *   ** * ** a prefix of %s",a,b);
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*  **** *  **  ** * **** * ******* *  ****** * * *   *    *** **
*      * *  *   ** *  * ** ** *** **     **  *  *   * ** ** 
***  ***  *   * *** * ****** ** ** *** ***********
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**  ***    * * **   * **  * **** ****** * * *   * ****    *** ***   * **  **  * ***** 
 ***   * ** * *  *** *  ** *   *     ****    **  ** 
    }


}

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])
{
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**  * ******   * *   * ****   ***  count=0;
 * *  ** * **   * **  *  *     len;

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

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


* * * *    ****  ** * * **    
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 * *   ***    **   **   * *** ****  ** ***   **   * 1;
 *** * * * **** **  **  
 * *    *  *    *   * *       * 

   return 0;
}


int main()
{
*  * ** **  *     ***** *  **  *** *** a[100];
   * * ** ****   * *  * * ***  ** **  b[100];


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

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

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