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