cuda::isqrt

template <typename T>
[[nodiscard]] __host__ __device__ inline constexpr
T isqrt(T value) noexcept;

The function computes the integer square root of the input value rounded down.

Parameters

• value: The input value.

Return value

• The square root value of the input value rounded down.

Constraints

• T is an integer type.

Preconditions

• value is non-negative.

Example

#include <cuda/cmath>
#include <cuda/std/cassert>

__global__ void isqrt_kernel() {
    assert(cuda::isqrt(1) == 1);
    assert(cuda::isqrt(4) == 2);
    assert(cuda::isqrt(42) == 6);
    assert(cuda::isqrt(99) == 9);
    assert(cuda::isqrt(100) == 10);
}

int main() {
    isqrt_kernel<<<1, 1>>>();
    cudaDeviceSynchronize();
}

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