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);
         ^