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);
         ^