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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**  *  ** ****    *   * ***
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**** * * * *  *  * **    **** **  *  ******* *   *  **  **  ** * ****   ****** *   ***** ***    * *  *   **     * *  ** * 1;
*** * ****  **  ****  * * ****** *      * **  *** ** *   **    * **       *** **  *  *** **
* *    ** *** ** *** *     *  ** *  *    **   * 
 *      ****    **  ***   ****  ****  *  *  ** * *  ** *  **     * * if(p[i]!=s[i])
**  ****  **** *** *  *   *      *  * ** *         
*  * * *      *  *    * * *  ** *** ** **   *   * ***   ** *  *    * ** ***  ***    0;
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 ***** *** ***  * **  ** ** *  ** 
}


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);
         ^