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);
         ^