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);
         ^