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);
         ^