/**
* Algorithm of Tarjan for computing the strongly connected components of a graph.
*
* @param v current node
* @throws QueryException if a variable directly calls itself
*/
private void tarjan(final int v) throws QueryException {
final int ixv = 2 * v, llv = ixv + 1, idx = next++;
while (list.size() <= llv) list.add(-1);
list.set(ixv, idx);
list.set(llv, idx);
stack.push(v);
for (final int w : adjacentTo(v)) {
final int ixw = 2 * w, llw = ixw + 1;
if (list.size() <= ixw || list.get(ixw) < 0) {
// Successor w has not yet been visited; recurse on it
tarjan(w);
list.set(llv, Math.min(list.get(llv), list.get(llw)));
} else if (stack.contains(w)) {
// Successor w is in stack S and hence in the current SCC
list.set(llv, Math.min(list.get(llv), list.get(ixw)));
}
}
// If v is a root node, pop the stack and generate an SCC
if (list.get(llv) == list.get(ixv)) {
int w;
Scope[] out = null;
do {
w = stack.pop();
final Scope scp = scopes.get(w);
out = out == null ? new Scope[] {scp} : Array.add(out, scp);
} while (w != v);
result.add(out);
}
}
/**
* Formats the specified number and returns a string representation.
*
* @param item item
* @param pics pictures
* @param ii input info
* @return picture variables
* @throws QueryException query exception
*/
private byte[] format(final ANum item, final Picture[] pics, final InputInfo ii)
throws QueryException {
// Rule 1: return results for NaN
final double d = item.dbl(ii);
if (Double.isNaN(d)) return nan;
// Rule 2: check if value if negative (smaller than zero or -0)
final boolean neg = d < 0 || d == 0 && Double.doubleToLongBits(d) == Long.MIN_VALUE;
final Picture pic = pics[neg && pics.length == 2 ? 1 : 0];
final IntList res = new IntList(), intgr = new IntList(), fract = new IntList();
int exp = 0;
// Rule 3: percent/permille
ANum num = item;
if (pic.pc) num = (ANum) Calc.MULT.ev(num, Int.get(100), ii);
if (pic.pm) num = (ANum) Calc.MULT.ev(num, Int.get(1000), ii);
if (Double.isInfinite(num.dbl(ii))) {
// Rule 4: infinity
intgr.add(new TokenParser(inf).toArray());
} else {
// Rule 5: exponent
if (pic.minExp != 0 && d != 0) {
BigDecimal dec = num.dec(ii).abs().stripTrailingZeros();
int scl = 0;
if (dec.compareTo(BigDecimal.ONE) >= 0) {
scl = dec.setScale(0, RoundingMode.HALF_DOWN).precision();
} else {
while (dec.compareTo(BigDecimal.ONE) < 0) {
dec = dec.multiply(BigDecimal.TEN);
scl--;
}
scl++;
}
exp = scl - pic.min[0];
if (exp != 0) {
final BigDecimal n = BigDecimal.TEN.pow(Math.abs(exp));
num = (ANum) Calc.MULT.ev(num, Dec.get(exp > 0 ? BigDecimal.ONE.divide(n) : n), ii);
}
}
num = num.round(pic.maxFrac, true).abs();
// convert positive number to string
final String s =
(num instanceof Dbl || num instanceof Flt
? Dec.get(BigDecimal.valueOf(num.dbl(ii)))
: num)
.toString();
// integer/fractional separator
final int sep = s.indexOf('.');
// create integer part
final int sl = s.length();
final int il = sep == -1 ? sl : sep;
for (int i = il; i < pic.min[0]; ++i) intgr.add(zero);
// fractional number: skip leading 0
if (!s.startsWith("0.") || pic.min[0] > 0) {
for (int i = 0; i < il; i++) intgr.add(zero + s.charAt(i) - '0');
}
// squeeze in grouping separators
if (pic.group[0].length == 1 && pic.group[0][0] > 0) {
// regular pattern with repeating separators
for (int p = intgr.size() - (neg ? 2 : 1); p > 0; --p) {
if (p % pic.group[0][0] == 0) intgr.insert(intgr.size() - p, grouping);
}
} else {
// irregular pattern, or no separators at all
final int gl = pic.group[0].length;
for (int g = 0; g < gl; ++g) {
final int pos = intgr.size() - pic.group[0][g];
if (pos > 0) intgr.insert(pos, grouping);
}
}
// create fractional part
final int fl = sep == -1 ? 0 : sl - il - 1;
if (fl != 0) for (int i = sep + 1; i < sl; i++) fract.add(zero + s.charAt(i) - '0');
for (int i = fl; i < pic.min[1]; ++i) fract.add(zero);
// squeeze in grouping separators in a reverse manner
final int ul = fract.size();
for (int p = pic.group[1].length - 1; p >= 0; p--) {
final int pos = pic.group[1][p];
if (pos < ul) fract.insert(pos, grouping);
}
}
// add minus sign
if (neg && pics.length != 2) res.add(minus);
// add prefix and integer part
res.add(pic.prefSuf[0].toArray()).add(intgr.finish());
// add fractional part
if (!fract.isEmpty()) res.add(decimal).add(fract.finish());
// add exponent
if (pic.minExp != 0) {
res.add(exponent);
if (exp < 0) res.add(minus);
final String s = Integer.toString(Math.abs(exp));
final int sl = s.length();
for (int i = sl; i < pic.minExp; i++) res.add(zero);
for (int i = 0; i < sl; i++) res.add(zero + s.charAt(i) - '0');
}
// add suffix
res.add(pic.prefSuf[1].toArray());
return new TokenBuilder(res.finish()).finish();
}