maul8

#include <float.h>
#include <math.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

enum {
    FRAC_MASK = (1 << 23) - 1,
    FRAC_WIDTH = 23,
    EXP_MASK = (255 << 23),
    SIGN_MASK = (1 << 31),
    MAX_EXP = 255
};

union {
    float fl;
    uint32_t dw;
} f;

void f_mul8(float *x) {
    if (isnan(*x)) {
        return;
    }
    f.fl = *x;
    uint32_t exp = (f.dw & EXP_MASK) >> FRAC_WIDTH;
    exp += 3;
    if (exp >= MAX_EXP) {
        *x = (f.dw | SIGN_MASK) | EXP_MASK;
        return;
    }
    f.dw = (f.dw & SIGN_MASK) | (exp << FRAC_WIDTH) | (f.dw & FRAC_MASK);
    *x = f.fl;
}

int main() {
    float num;
    if (scanf("%f", &num) == 1) {
        f_mul8(&num);
        printf("%f ", num);
    }
}