Any way faster than pow() to compute an integer power of 10 in C++?

Question

I know power of 2 can be implemented using << operator. What about power of 10? Like 10^5? Is there any way faster than pow(10,5) in C++? It is a pretty straight-forw

Answer 1

Now, with constexpr, you can do like so:

constexpr int pow10(int n) {
    int result = 1;
    for (int i = 1; i<=n; ++i)
        result *= 10;
    return result;
}

int main () {
    int i = pow10(5);
}

i will be calculated at compile time. ASM generated for x86-64 gcc 9.2:

main:
        push    rbp
        mov     rbp, rsp
        mov     DWORD PTR [rbp-4], 100000
        mov     eax, 0
        pop     rbp
        ret