Submission 9c176410...
pragma solidity 0.4.24;
contract Sort {
function sort(uint[] input) public pure returns(uint[]) {
uint length = input.length;
// Trivial cases
if (length <= 1) { return input; }
uint i;
// Count ordered elements
uint asc = 0;
for (i = length - 1; i > 0; i--) {
if (input[i] >= input[i - 1]) { asc++; }
}
// If Almost entirely reversed, reverse it
if (asc < (length / 4)) {
uint end = length / 2;
for (i = 0; i < end; i++) {
(input[i], input[length - i - 1]) = (input[length - i - 1], input[i]);
}
asc = length - asc - 1;
}
// Already sorted
if ((asc + 1) == length) { return input; }
// QuickSort
if (asc + 8 < length) {
quicksort(input);
}
// Linear Insertion Sort
// See: https://en.wikipedia.org/wiki/Insertion_sort
for (i = 1; i < length; i++) {
uint256 tmp = input[i];
int256 j = int(i) - 1;
while (j >= 0 && input[uint(j)] > tmp) {
input[uint(j) + 1] = input[uint(j)];
j--;
}
input[uint(j) + 1] = tmp;
}
return input;
}
// See: https://www.geeksforgeeks.org/iterative-quick-sort/
function quicksort(uint[] A) internal pure {
uint stackHi = 0;
uint stackLo = 0;
uint lo = 0;
uint hi = A.length - 1;
while (true) {
uint pivot = A[(lo + hi) / 2];
// Note: May temporarility overflow below 0, but will be corrected in the first loop
uint i = lo - 1;
uint j = hi + 1;
while (true) {
uint a;
uint b;
while(true) {
a = A[++i];
if (a >= pivot) { break; }
}
while(true) {
b = A[--j];
if (b <= pivot) { break; }
}
if (i >= j) {
pivot = j;
break;
}
A[i] = b;
A[j] = a;
}
if (pivot > lo + 8) {
//if (pivot > lo) {
if (pivot + 1 + 8 < hi) {
//if (pivot + 1 < hi) {
stackLo *= 0x10000;
stackLo |= pivot + 1;
stackHi *= 0x10000;
stackHi |= hi;
}
hi = pivot;
} else if (pivot + 1 + 8 < hi) {
//} else if (pivot + 1 < hi) {
lo = pivot + 1;
} else if (stackHi != 0) {
hi = stackHi & 0xffff;
stackHi /= 0x10000;
lo = stackLo & 0xffff;
stackLo /= 0x10000;
} else {
break;
}
}
}
}