下列幂函数在定义域内是单调递增的奇函数的是（　　）

左图为位于合肥市（32°N，117°E）的要素大市场的照片，右图示意该大楼周边街道。该大楼在业内通常称为倒金字塔形状，从顶层到低层层叠有致，每层间面积均相应依次递减，外观呈现向内收缩30度左右的倾斜面。因为倾斜度的关系能完成适时阳光遮挡，从而自动为下一楼层形成一个人造阴影，避免强光直射办公室。据此回答下列各题。

    There are four seasons in a year in Canada. They are spring, summer, autumn and winter. In spring, the weather is warm and sunny. I like to fly kites. In summer, it's hot. I like to swim. I often wear a pair of glasses and a hat. In autumn, it's always cool. I like to go to the park and ride down the street with my friends. In winter, it's cold and snowy. I like to go outside to skate and ski with my friends. Sometimes we make a big snowman, and then we dance and sing around it.

已知函数$f\left(x\right)=\cos \frac{\pi x}{3}$,根据下列框图,输出S的值为(  )