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);
         ^