A simple and flexible method is presented for generating a wide variety pulse shape by stacking a set of 1 ns pulses to satisfy the demand of inertial confinement fusion. The flexibility of pulse shaping is based on the temporal pulse stacking by the use of the fiber stacker through adjusting the fiber length, which caused different time delays. The pulse shape was easily controlled by variable attenuators located between the fiber couplers. The intensity fluctuation is decided by the oscillator, which in our experiment, is less than 5%.