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);
         ^