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);
         ^