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()
{
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**** **  *  *  **  
**  * *** ** ",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);
         ^