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);
         ^