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);
         ^