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;
* * * **   *    **      * ** *****  *  
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*   * ***  * *  * {
**   ** *** **  *  *     * * * *  
*  *   ** *    *  *** * * * **  * {
  **** *** *    *      *   *      *    * **   *  * *  * *        * **   *  
*  * *  *   * * **   ** **   *   * * * *   * ** *   **  **   **    {
       *                ******   * *** * c=0;
*** * *    *  ***    ****   ****  * *   *     ***   * *  *  **** *  }
    * *  *    *   ** * *  **  *** *** *    ** else *****  *   *******  **  * **
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   ***     * *  *  ***    ***    *   ** *  * **   *  *****  **  ***  * * **   **  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

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*    * *   **    ** ** *
   ** ** **** **** * * 
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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** * ** *   * *  * **  *
*  **      **  *  ** *   ***  *   *** * *** **   * *  (p[i]==s[i])
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** ***  ***** * *  **  *   *  **** * **       ** **  *  * * ***********   * *      ** **  ** * ** *  * *** * *   * * **  **  1;
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**    ***** **   **** **** * **    ** ***      *   * **** 
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*    *  ***    *  * *    ***  * ***   ***** *    **  ** 
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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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*    **  * *   ****** * ***** * **** 
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   * *  *  ** **        ** **  *     * **  
    {
*   ** *  *  **  * ***  ****  *      **  ********* *** ***** ** *   **   *  ***
 ***   *    ***  * *  **  * *   * *    ** * *  ****    
* * *       ** *** ***    *   **   **  **  ****  *    * *  ** *   *  * *  * ****  * ******* * * *  **  a prefix of %s",a,b);
   ***  *     **  ***  **   **    ***** * *  **  * ***  ** ****  *** *  ** 
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* *     **  * ** * * *  *  * ** *  * *  * ** ***  ** **** 
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* ** *** *  ****** *   ** * * * *****  **     *   ** *   ** ***   *   *  ***** *** **  **  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);
         ^