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;
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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;

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

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


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