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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* **     *** *   **    **  **  * *   **** *   * ***  ** **** **  * **   *   * 
*  **   *  ** *** ***   **   * *** * ***    ** *** * *** *  **  ** *     * *  ** ** *** *  *** *****  ***  1;
**   *  *  *  ******   * ****    *  * ** **    *****     * ****   * **  **** 
* * * * **   ** ** **   *** **** ** * ***   *  ** * * * 
 *       * * *  * * *   *   * **  ***  *   * *** *    * if(p[i]!=s[i])
    **  ** **  ***  ** **   *** *** ** * *** *   * * 
** *  *     * * ***  * * *  *** **** * * *** ***   **  ****   *****    ****  * * * 0;
* *    ********  *  *  ******  *****  ** **    ***
* ** * **     **  ****  * 
}


int main()
{
 * **** **  *
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** ** * *  **** ",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;
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* * ** **** * *   *  ***   **   * **  * 
* *     ****  *** * **** ****  
   *  * ** * *   *  **** ** * **     *** * 
    {
 * ***  ** * ** **    * * * ** *  ***     ***  * *     ** *   
*******   *   *       *  **  * *  *** ** *  * **  * ***
 **** **     *     ** *    *** *********  *  *****  *  **  ** *  *    * **** * **   *  **    * 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);
         ^