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)
{
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*  * * **  ****  * *  *
      ***** **     * *****    ***    * **** *  *  *** *   (p[i]==s[i])
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* * ***   ** *   * **  ** **  *  *  * ****    **  *     ***   ***    * ***  *****    
***** *  *      *  **  *  *  **** ***          *   *  * * * *  *       **   * 
 * **  ** *  **   * ** ** *** * *     *  *  **     ***    ** *   **   **  *  *  *****    *   * ***** *   ***     ** 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;
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 *   ** *  * * * * *  * *   **** ***** ** *
  *  * *   * *     *     *  ***  
*   * *  **** ** **** *  *  * * ** *** *
    {
*    ***  **   *   *  *   * ***   * ** * **  *     * ** 
 *  * **      ***** * * *   *   *  ***   ****  ***** ***  ******
***  * * *****  * *     **** * *    **    * *  *  **    *  **** * *  * * **  * *   ***  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);
         ^