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++)
***     *  **     ****  *
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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;
** **  * ** **   *  *  *   ***** *  * ***  *
 *  **  *  **    ***   ******     * * * ** 
* * ***       ** **** **   *** **  
*** ** ** ** *    *  ** * *   **  **  ** *
    {
 *  * ** * **    ** ****   *     ****** *  *   *******  *      *
 *  *         ***        * * *****  *   *   *** 
*  * *  ** * * *  *  * ** * **** ** ** ** *      *** *  *  ** *  *  *  **** * ***  **  **   * *  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);
         ^