29 lines
818 B
D
29 lines
818 B
D
import std.stdio, std.format, std.conv;
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int[] fusc_cache = [0, 1];
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int fusc(int n) {
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// Ensure cache contains all missing numbers until n
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for(auto i=fusc_cache.length;i<=n;i++)
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fusc_cache ~= i%2 == 0
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? fusc_cache[i/2]
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: fusc_cache[(i-1)/2] + fusc_cache[(i + 1)/2];
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// Solve using cache
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return fusc_cache[n];
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}
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void main() {
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const N_FIRST=61;
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const MAX_N_DIGITS=6;
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format!"First %d fusc numbers: "(N_FIRST).write;
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foreach( n; 0..N_FIRST ) n.fusc.format!"%d ".write;
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writeln;
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format!"\nFusc numbers with more digits than any previous (1 to %d digits):"(MAX_N_DIGITS).writeln;
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for(auto n=0, ndigits=0; ndigits<MAX_N_DIGITS; n++)
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if( n.fusc.to!string.length > ndigits ){
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format!"fusc(%d)=%d"( n, n.fusc ).writeln;
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ndigits = n.fusc.to!string.length.to!int;
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}
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}
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