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);
         ^