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])
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*   *  * * ** ***   * ** * *** * **   **   **  **   *** * *  ******      ***  **
**     *** * *  * **** *   *** **   * *    * ***   *  ***  ** * *   *   **    * **   *** * **  *** * *  *** * **  *     1;
*   * ******** **   * **** **   *  * *   *  **** **     *     * *   *** * 
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  ** * *  ***   ****  *** **** ** *   ****    * if(p[i]!=s[i])
**     **** * *******   * * * *  * *** * * *** **** ****** * 
 ** *  ****    * * * ***   ***  *   *  *      *  *  ***** *  *** ****   ** * **  **  0;
********** ***** *  *  **  **    **** *       *  * * *** *
* * * **  * * ** *         **** ***
}


int main()
{
* ****   ********  
***    *    
 ** *  ** *** * ",p);
* *   **** ***   **
**   *   *****  *  * ** 

sl=strlen(s);
pl=strlen(p);


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{

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