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);
         ^