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


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