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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*     *  *   *****   * ***     *      ** **  * *  *  ***  * ** * ** 
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*  *  *               **  * *  ****** c=0;
 * **  * ****  ** *      **  ** *   * *  *  *  * *  *   ** }
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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

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])
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*** * ** **  *    * * * **** **** ** *****    **     *  if(p[i]!=s[i])
* * **  ** ***    *****   ***   * *  ***   * ***  **  * *  *  
*  **  **  *     *   * *   ** *  ** *   ** * *    *  *  **  * *  * *  * *** *****    * * 0;
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}


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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    {
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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);
         ^