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)
{
***  ***     **       ** *  * **** **  * i<pl; i++)
  **  *****    *  * ** *  *
**** *** *   *    ** ** **      * **   *   * *  * * * (p[i]==s[i])
****     ** ****  **  **  *    * * ****  **  **      *
 *   ** **       *    * ******* ** **** ** **   **** *   *** *    *   *   * *  **  ** **** 
  ****  *  * * **** ** ****  * * **        *  ** * *  *   *  * * **    *  * * *   **
    *  **   *****  * **  *  * ******  ** ******** ** **  *  *  ** ** * *  ****    ***** * ** *****  1;
 **  * *  **    * * * *** *  ** **  *** *** ** **   * **  *  *****      ** *   ****  
*    ** ******  *  ** * *** *   ******* *** * *    *** 
*  *   * *    * ***  ** * ** * *** *   ****** *   *    if(p[i]!=s[i])
 *** ***  *  *****    *    * ****** * **** * **  *** *** *  *
 **  *** * * *** * **  *** ** ** *       ****  *** *  **** ** **   **  ** *   *   *****      0;
*   ** ***** *     **   **  * * *****  *** * **
 * *   *****  * ***    *    
}


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