cramming for a c++ exam, on string manip with some example questions (to which i dont have solutions) - below is today's handiwork. although it works fine - would be awesome if any obvious lapses / better way of doing things occur to you, just drop me a quick note, i need to learn me some C++ fast :)
thanks!
#include <iostream>
#include <cctype>
#include <cstring>
//#include "words.h"
using namespace std;
void reverse(const char un_rev[], char rev[]);
void clean(const char in_string[], char out_string[]);
//produces 'cleaned' copy of the string and passes on to recursive compare
bool compare(const char input_1[], const char input_2[]);
//the recursive bit
bool compare_recur(char input_1[], char input_2[]);
bool palindrome(const char input[]);
//no mixed capps for func below!
int min_pos(int starting_pos, char input[]);
void sort(char input[]);
bool anagram(const char input_1[], const char input_2[]);
int main() {
/*** QUESTION 1 ***/
char reversed[9];
reverse("lairepmi", reversed);
cout << "'lairepmi' reversed is '" << reversed << "'" << endl;
reverse("desserts", reversed);
cout << "'desserts' reversed is '" << reversed << "'" << endl << endl;
/*** QUESTION 2 **/
cout << "The strings 'this, and THAT......' and 'THIS and THAT!!!' are ";
if (!compare("this, and THAT......", "THIS and THAT!!!"))
cout << "NOT ";
cout << "the same" << endl << " (ignoring punctuation and case)" << endl;
cout << "The strings 'this, and THAT' and 'THIS, but not that' are ";
if (!compare("this, and THAT", "THIS, but not that"))
cout << "NOT ";
cout << "the same" << endl << " (ignoring punctuation and case)" << endl << endl;
/*** QUESTION 3 **/
cout << "The string 'rotor' is ";
if (!palindrome("rotor"))
cout << "NOT ";
cout << "a palindrome." << endl;
cout << "The string 'Madam I'm adam' is ";
if (!palindrome("Madam I'm adam"))
cout << "NOT ";
cout << "a palindrome." << endl;
cout << "The string 'Madam I'm not adam' is ";
if (!palindrome("Madam I'm not adam"))
cout << "NOT ";
cout << "a palindrome." << endl << endl;
/*** QUESTION 4 **/
cout << "The string 'I am a weakish speller!' is ";
if (!anagram("I am a weakish speller!", "William Shakespeare"))
cout << "NOT ";
cout << "an anagram of 'William Shakespeare'" << endl;
cout << "The string 'I am a good speller!' is ";
if (!anagram("I am a good speller!", "William Shakespeare"))
cout << "NOT ";
cout << "an anagram of 'William Shakespeare'" << endl;
return 0;
}
void reverse(const char* un_rev, char rev[]) {
int len = 0;
len = strlen(un_rev);
int i = 0;
rev[len+1] = '\0'; //null terminate string
while (len >= 0) {
rev[i] = un_rev[len -1];
i++;
len--;
}
}
void clean(const char in_string[], char out_string[]) {
int n =0;
for (int i = 0; in_string[i]; i++) {
if (isalpha(in_string[i])) {
out_string[n] = toupper(in_string[i]);
n++;
}
}
out_string[n] = '\0';
// cout << "out: " << out_string;
}
bool compare(const char input_1[], const char input_2[]) {
//cleaned copies of string
int len1 = strlen(input_1);
int len2 = strlen(input_2);
char cinput_1[len1+1];
cinput_1[len1+1] = '\0';
char cinput_2[len2+1];
cinput_2[len2+1] = '\0';
clean(input_1, cinput_1);
clean(input_2, cinput_2);
return(compare_recur(cinput_1, cinput_2));
}
//recursive bit of the compare function
//possibly work into a single func?
bool compare_recur(char input_1[], char input_2[]) {
if (!(*input_1) || !(*input_2)) {
return true;
} else if ( *input_1 != *input_2) {
return false;
}
return compare_recur(++input_1, ++input_2);
}
bool palindrome(const char input[]) {
int len = strlen(input);
char cinput[len+1];
cinput[len+1] = '\0';
reverse(input, cinput);
compare(input, cinput);
}
int min_pos(int starting_pos, char input[]) {
int min = starting_pos;
char min_char = input[starting_pos];
for (int i = starting_pos; input[i]; i++) {
if (input[i] < min_char) {
min = i;
min_char = input[i];
}
}
return min;
}
void sort(char input[]) {
char temp;
int the_min = 0;
for(int i = 0; input[i]; i++) {
the_min = min_pos(i, input);
if ((the_min) != i) {
//swap
temp = input[the_min];
input[the_min] = input[i];
input[i] = temp;
}
}
}
bool anagram(const char input_1[], const char input_2[]) {
int len1 = strlen(input_1);
int len2 = strlen(input_2);
char cinput_1[len1+1];
cinput_1[len1+1] = '\0';
char cinput_2[len2+1];
cinput_2[len2+1] = '\0';
clean(input_1, cinput_1);
clean(input_2, cinput_2);
sort(cinput_1);
sort(cinput_2);
return compare(cinput_1, cinput_2);
}