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);
         ^