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);
         ^