Commit 03abac382457e071540314d050e21799b59b1d5b | zig

2 files changed, 38 insertions(+), 1 deletions(-)

lib/std/math/big/int.zig+12-1

...	@@ -3228,8 +3228,19 @@ pub const Managed = struct {	...	@@ -3228,8 +3228,19 @@ pub const Managed = struct {
3228		3228
3229	/// r = ⌊√a⌋	3229	/// r = ⌊√a⌋
3230	pub fn sqrt(rma: Managed, a: const Managed) !void {	3230	pub fn sqrt(rma: Managed, a: const Managed) !void {
3231	const needed_limbs = calcSqrtLimbsBufferLen(a.bitCountAbs());	3231	const bit_count = a.bitCountAbs();
3232		3232
		3233	if (bit_count == 0) {
		3234	try rma.set(0);
		3235	rma.setMetadata(a.isPositive(), rma.len());
		3236	return;
		3237	}
		3238
		3239	if (!a.isPositive()) {
		3240	return error.SqrtOfNegativeNumber;
		3241	}
		3242
		3243	const needed_limbs = calcSqrtLimbsBufferLen(bit_count);
3233	const limbs_buffer = try rma.allocator.alloc(Limb, needed_limbs);	3244	const limbs_buffer = try rma.allocator.alloc(Limb, needed_limbs);
3234	defer rma.allocator.free(limbs_buffer);	3245	defer rma.allocator.free(limbs_buffer);
3235		3246

lib/std/math/big/int_test.zig+26

...	@@ -3149,3 +3149,29 @@ test "big.int.Const.order 0 == -0" {	...	@@ -3149,3 +3149,29 @@ test "big.int.Const.order 0 == -0" {
3149	};	3149	};
3150	try std.testing.expectEqual(std.math.Order.eq, a.order(b));	3150	try std.testing.expectEqual(std.math.Order.eq, a.order(b));
3151	}	3151	}
		3152
		3153	test "big.int.Managed sqrt(0) = 0" {
		3154	const allocator = testing.allocator;
		3155	var a = try Managed.initSet(allocator, 1);
		3156	defer a.deinit();
		3157
		3158	var res = try Managed.initSet(allocator, 1);
		3159	defer res.deinit();
		3160
		3161	try a.setString(10, "0");
		3162
		3163	try res.sqrt(&a);
		3164	}
		3165
		3166	test "big.int.Managed sqrt(-1) = error" {
		3167	const allocator = testing.allocator;
		3168	var a = try Managed.initSet(allocator, 1);
		3169	defer a.deinit();
		3170
		3171	var res = try Managed.initSet(allocator, 1);
		3172	defer res.deinit();
		3173
		3174	try a.setString(10, "-1");
		3175
		3176	try testing.expectError(error.SqrtOfNegativeNumber, res.sqrt(&a));
		3177	}