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;
* * **** **   *** *     * * ****   * ** **  **
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***** * * ** *   *   **      *** *   
* ** ***   *  * {
*   * *     *  *  ** *   **  *****  **
* *  * **** *      *  ** {
  *    **  ** **     ***  *****  *  **** * * *** **  ***     * ** 
  **      *   ***** *   ** *       *   * *  *  *** *    * *   {
 ****  *                **    **    **  *  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

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