Scatter plot of the duration of superflares as a function of the bolometric energy. Filled squares and small crosses indicate superflares on G-type main sequence stars detected from short- and long-cadence data, respectively. We used e-folding decay time as the flare duration. Dotted line indicates the linear regression for the data of superflares from short-cadence data. The power-law slope of the line is 0.39±0.03.