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);
         ^