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#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <array>
#include <bitset>
#include <functional>
#include <iostream>
#include <list>
#include <map>
#include <set>
#include <thread>
#include <boost/integer.hpp>
#include "mmalloc.hpp"
#include "timer.hpp"
using namespace std;
using boost::optional;
#ifndef BIT_WIDTH
#define BIT_WIDTH 30
#endif
typedef typename boost::uint_t<BIT_WIDTH + 1>::least State;
const State logState = BIT_WIDTH;
const State maxState = (State) 1 << logState;
bitset<8> rule(110);
State update(State s) {
State r(0);
bitset<logState> b(s);
for (unsigned i=0; i<logState; i++)
r |= rule[1 * b[(i + logState - 1) % logState]
+ 2 * b[i]
+ 4 * b[(i + 1) % logState]] << i;
return r;
}
typedef array<State, maxState> Trans;
typedef array<uint8_t, maxState> pbitset;
void iterState(function<void(int)> f, optional<string> msg = optional<string>(), bool parallel = false) {
PerfPrinter perfPrinter(msg);
int numThreads=1;
if (parallel) {
numThreads = min((State) thread::hardware_concurrency(), maxState);
}
list<thread*> tasks;
for (int t=0; t<numThreads; t++) {
tasks.push_front(new thread([=]{
for (State s = maxState / numThreads * t;
s < ((t == numThreads - 1) ? maxState : (maxState / numThreads * (t+1)));
s++)
f(s);
}));
}
for (; !tasks.empty(); tasks.front()->join(), delete tasks.front(), tasks.pop_front());
}
void iterTrans(int times, function<void(int)> f, optional<string> msg = optional<string>(), bool parallel = false) {
PerfPrinter perfPrinter(msg);
auto msg2 = [=,&msg] (int i) {
return msg ? (*msg + string(" ") + to_string(times-i) + string("/") + to_string(times)) : msg; };
while (times--) {
iterState(f, msg2(times), parallel);
}
}
void init(Trans &t) {
iterState([&](int s) {
t[s] = update(s);
}, (string) "single step transition table", true);
}
void findCycle(Trans &t, Trans &c, pbitset &reachable) {
// compute reachability
iterState([&](int s) {
reachable[t[s]] = 1;
}, (string) "reachability", true);
// forward to t=maxState; now every state is in a cycle
iterTrans(logState, [&](int s) {
t[s] = t[t[s]];
}, (string) "fwd time");
// compute loop id (lowest occuring state no): go through the loop again and
// record the lowest occuring state number
iterState([&](int s) {
c[s] = t[s];
}, (string) "init cycles", true);
iterTrans(logState, [&](int s) {
c[s] = min<State>(c[s], c[t[s]]);
t[s] = t[t[s]];
}, (string) "cycles");
}
void cycleStat(Trans &c, pbitset &reachable) {
struct Stat {
State basin, len, eden, minState;
Stat() : basin(0), len(0), eden(0), minState(maxState) {}
};
map<State, Stat> cyc;
// How big is the basin of attraction?
// How many garden of eden states does it contain?
iterState([&](int s) {
cyc[c[s]].basin++;
if (!reachable[s])
cyc[c[s]].eden++;
}, (string) "basin & eden");
// how long is the cycle, what is the actual minimal state
{ PerfPrinter perfPrinter((string) "cycle length");
for (auto i : cyc) {
Stat &s = cyc[i.first];
State cur, start;
cur = start = c[i.first];
do {
s.len++;
s.minState = min(s.minState, cur);
cur=update(cur);
} while (cur != start);
}}
// find duplicates cycles (only bitshifted)
map<State, set<State>> ccyc;
{ PerfPrinter perfPrinter((string) "find duplicate cycles");
auto canonize = [](State s) {
State cs = s;
for (State i=0; i<logState; i++)
cs = min(cs, (((s<<i) | (s>>(logState-i))) & (maxState - 1)));
return cs;
};
for (auto i : cyc) {
ccyc[canonize(i.second.minState)].insert(i.first);
}}
// print it
for (auto i : ccyc) {
Stat &s = cyc[*(i.second.begin())];
cout << bitset<logState>(i.first) << "\t"
<< i.second.size() << "\t"
<< s.len << "\t"
<< s.basin << "\t"
<< s.eden << "\t"
<< i.first << endl;
}
}
void print(Trans &t) {
for (auto s : t)
cout << bitset<logState>(s) << endl;
}
void printTraj(State s, int count) {
while (count--) {
cout << bitset<logState>(s) << endl;
s = update(s);
}
}
int main(int argc, char **argv) {
assert(argc >= 2);
rule = atoi(argv[1]);
if (!strcmp(argv[2], "traj")) {
assert(argc == 5);
printTraj(atoi(argv[3]), atoi(argv[4]));
}
if (!strcmp(argv[2], "cycle")) {
Trans *t = mmalloc<Trans>(),
*c = mmalloc<Trans>();
pbitset *r = mmalloc<pbitset>();
init(*t);
findCycle(*t, *c, *r);
cycleStat(*c, *r);
}
return 0;
}
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