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