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);
         ^