If the equation  $x^3-3x+1=0$ has three real roots  $x_1,x_2,x_3$, where  $x_1<x_2<x_3$, then the value of  $(\left\{x_1\right\}+\left\{x_2\right\}+\left\{x_3\right\})$ is equal to:
[Note: {x} denotes the fractional part of x.]