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);
         ^