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);
         ^