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])
*    ** *  ** **  *   * **** *  *  *  *    ****    **** 
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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);
         ^