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])
**   *  * **    ** *** ***   * ** *** ******** * *   * *** *
 ****  ** * ** ***  ** * * *  ***   *** **** **        *  *****    * * *    *  **
****** * * *** **  * ****** **  **** *  **  *****        * *   *** ** *   * 
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** **   **  **   *  **** ***  * * * * ********  ******  ** ***    *** ** *** *  *
 * ** **   ****** **   *     ** ***  * **  ******* **** *  ***
 * **   * *  ***       **  * * * *  * * ****** * **   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);
         ^