Floor (mathematics)

In mathematics and computer science, the floor function is the function that takes as input a real number ${\displaystyle x}$ and gives as output the greatest integer less than or equal to ${\displaystyle x}$, denoted ${\displaystyle {\text{floor}}(x)=\lfloor x\rfloor }$. Similarly, the ceiling function maps ${\displaystyle x}$ to the least integer greater than or equal to ${\displaystyle x}$, denoted ${\displaystyle {\text{ceiling}}(x)=\lceil x\rceil }$.

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