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);
         ^