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)
{
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*** ***  ******    **** **  
*  ******* *  ** **  ****  *  *    **  ** * **   *     *   (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;
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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);
         ^