int Float2Int(float f)
{
    return *(int*)&f;
}
int main(int argc, char* argv[])
{
    printf("%d", Float2Int(-100.56));
    return 0;
}

#include <stdio.h>
int Float2Int(float f)
{
    return *(int*)&f;
}
float Int2Float(int i)
{
    return *(float*)&i;
}
int main(int argc, char* argv[])
{
    float f = -100.56;
    int i = Float2Int(f);
    float i2f = Int2Float(i);
    printf("%d\n", i);
    printf("%f\n", i2f);
    return 0;
}