Problem 44375. Missing five
Convert decimal numbers to a base9 notation missing the digit 5
Too many fivethemed problems? Wondering whether everything would be simpler if we just got rid of the digit 5? Let's try!
In a world without 5's, positive integers may be represented using a base9 notation that uses only the digits 0, 1, 2, 3, 4, 6, 7, 8, and 9. We'll call this the "missing5" notation. The following list shows the first 100 positive numbers (i.e. 1 through 100) using "missing5" notation:
'1' '2' '3' '4' '6' '7' '8' '9' '10' '11' '12' '13' '14' '16' '17' '18' '19' '20' '21' '22' '23' '24' '26' '27' '28' '29' '30' '31' '32' '33' '34' '36' '37' '38' '39' '40' '41' '42' '43' '44' '46' '47' '48' '49' '60' '61' '62' '63' '64' '66' '67' '68' '69' '70' '71' '72' '73' '74' '76' '77' '78' '79' '80' '81' '82' '83' '84' '86' '87' '88' '89' '90' '91' '92' '93' '94' '96' '97' '98' '99' '100' '101' '102' '103' '104' '106' '107' '108' '109' '110' '111' '112' '113' '114' '116' '117' '118' '119' '120' '121'
You may notice that this is simply the sorted list of positive numbers which do not contain the digit 5 in their decimal representation.
Your function should convert a positive decimal number N into its "missing5" notation. For example
dec2missing5(20)
should return '22' (the 20th positive number in missing5 notation), and
dec2missing5(100)
should return '121' (the 100th positive number in missing5 notation)
Good luck!
Small print: Your function may output a number, a char array, or a string; whatever you find simpler (e.g. in the example above, valid outputs are 121, '121', or "121"). Input numbers in testsuite are always relatively low valued positive integers (<10,000)
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6 Comments
Too bad this problem number has a '5' in it! :)
Ha Ha! six is the new 5!
function y = dec2missing5(x)
vec=[];
for i=1:15000
ele=num2str(i);
for j=1:length(ele)
if ele(j)=='5'
ele='';
break;
end
end
vec=[vec str2num(ele)];
end
y=vec(x);
end
why my solution is wrong???
You should return the last element of the vector
Need some trick for this problerm
Men you got so many test cases.First time I see a problerm w many test like this
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