UVA Problem 10082 – WERTYU Solution:
Click here to go to this problem in uva Online Judge.
Solving Technique:
Read the first paragraph and input section carefully. This is a simple mapping problem.
The problem is that the keyboard is broken and every key that was pressed its immediate right character was printed. So we have to reverse that procedure by mapping every input character to the character to its left based on the given keyboard.
Generating the keyboard layout is easy. We can use an array and lay them sequentially so when we find a character we print the character that is to its left.
If we only use array to layout keyboard then for every input we will need to search the whole array. We can fix this by mapping the layout array to another array beforehand only once. Then just access that index and print.
Here the first code below is mapping from predefined lookup table. The second one does brute force to find its match. Here I have used stringstream but c++ string or c char array can also be used.
Important: Be sure to add or print a new line after each output unless otherwise specified. The outputs should match exactly because sometimes even a space character causes the answer to be marked as wrong answer.
Input:
O S, GOMR YPFSU/
Output:
I AM FINE TODAY.
Code (Mapping from predefined Lookup table):
/**
* @author Quickgrid ( Asif Ahmed )
* @link https://quickgrid.wordpress.com
* Problem: UVA 10082 WERTYU ( using c++ string stream )
*/
#include<cstdio>
#include<sstream>
#include<iostream>
#define N 256
/**
* Predefined keyboard layout
*/
static const char kb[64] = "`1234567890-=QWERTYUIOP[]\ASDFGHJKL;'ZXCVBNM,./";
static char s[N], A[N];
void createTable(){
/**
* space character does not change
*/
A[' '] = ' ';
/**
* Create keyboard layout from broken keyboard
*/
register int i = 0;
for(; kb[i]; ++i)
A[kb[i+1]] = kb[i];
}
int main(){
std::ios_base::sync_with_stdio(NULL);
std::cin.tie(0);
register int i, j;
/**
* Create the keyboard layout beforehand
*/
createTable();
while(gets(s)){
/**
* Create a string stream from table to print all together
* We can also use string and add each character then print
*/
std::stringstream ss;
/**
* Lookup characters from predefined table
*/
for(i = 0; s[i]; ++i)
ss << A[s[i]];
std::cout << ss.str() << "\n";
}
return 0;
}
Code (Using Lookup Table):
/**
* @author Quickgrid ( Asif Ahmed )
* @link https://quickgrid.wordpress.com
* Problem: UVA 10082 WERTYU ( using c++ string stream )
*/
#include<cstdio>
#include<sstream>
#include<iostream>
static const char kb[64] = "`1234567890-=QWERTYUIOP[]\ASDFGHJKL;'ZXCVBNM,./";
static char s[256];
int main(){
std::ios_base::sync_with_stdio(NULL);
std::cin.tie(0);
register int i, j;
while(gets(s)){
std::stringstream ss;
for(i = 0; s[i]; ++i){
if(s[i] == ' ')
ss << ' ';
else{
/**
* Each character maps to a character in its left as defined
*/
for(j = 0; kb[j]; ++j){
if(s[i] == kb[j])
ss << kb[j - 1];
}
}
}
std::cout << ss.str() << "\n";
}
return 0;
}
Quickgrid 