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);
         ^