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

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 *  ***  *** *  *
 * **       ***  *

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
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*** ****** *   **  ***  **
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*  *** * **   *  **  ** *    * *  *   *          * **  *   * *  *    * ** *******   *  *
*  ** *   * ** *    ****  *  *** **** *  ******   **     *   *      *   *      *** **    ****  * ***  * **** ** 1;
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**  *  *** *  *     *   ****   ****    *   **
*** **  *     *   * * ***  * *  **   ***   **    * ***  * if(p[i]!=s[i])
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**     * *  ****** **  **  *   **  **** ** * *  * ** **  * ****  * *******  ** 0;
***       *  *  * **  *     ***  **** * **  *** *  ** 
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}


int main()
{
*  *    ****
**** * **  *     
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*** *   *  ** **  *
*  *  *  ** ***** * 

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;

   ** *** ** *  ** **    ***  * ***

   **** *** * ** * * ***** *****  **** *  * *
 *  *     ** *   * * *    *  * *
*    **** *    ****** * ** ***      ****  * *  * *** *  * * *     
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* *   *** *   ** * ****** ***    **  ** *   * * **** ** *
** ***  *****   **** * ** *


* ***   *******         *    * * ** *** *  
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 **** **   * *    ***   ***   *     * ****  * * *  * *  1;
* *    * ***   ***  * **
* **** ****  ***     *  *  

   return 0;
}


int main()
{
**** *** ***   ** * *******   a[100];
 * **  ***   ** ** *** **   * b[100];


**** * ****** *   * * * ***** ** * *      *    * ****
* * *   **** * **   * **** ****  ** **** * * ** *  **** *** 

   *    *   **  * * *  **   *  *  ****
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**** *** ** *      ***    * **    **  * 

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