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

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

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
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*  * ** ** ** **  ** *  **
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 ** * * ** **      *** * *  *    **   **  **  **   **   
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** **       **** **  *   ****  ***  *** ** ***     *   ** *  ** **** * **    ** ***  * * 0;
 * *** *  * * * *** *****    *   * **  ***    *   *   * *
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}


int main()
{
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*** **** ** *  ",p);
 **  * * *** * *    *
* * ** ** ** **  **   * * **

sl=strlen(s);
pl=strlen(p);


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{

*  * *    ***  *     **** * ***   *           * ** 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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*** ****     * **** ***  **  **  *********** 
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    {
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*    *    *   * *   **  * * ** *    *   *   * * ** 
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   * * * ***   * *     *  * ***** *** ****       * ***     *  * **   *** *** **
 **  ******  *  ***    *  *   *** ** *   *   ********
* *****  * *  * * ** *  **  ** * **  *** *  ** *  * *   ** 
*  *** *** * * *  **  *      ***  *     *  ** ***  * ****  
 ** ** ** *  * * *  *  ***   *** ***   *  ** **   ** * ** ** **  ** *  * *  ** *   * * ***  *    * 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])
{
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*  *****  * * ***** * *    count=0;
******   ***  * * * * * *  **** len;

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

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


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