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