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export function calculateStraightLineEquation(    point1: number[],    point2: number[],): [number, number, number] {    const [x1, y1] = point1;    const [x2, y2] = point2;    let a = 0;    let b = 0;    let c = 0;    if (x1 === x2) {        /* x=x1;    1x-x1=0    a=1    c=-x1    */        a = 1;        c = -x1;    } else if (y1 === y2) {        b = 1;        c = -y1;    } else {        /*    ax1+by1+c=0    ax2+by2+c=0
    a(x1-x2)+b(y1-y2)=0    a(x1-x2)=b(y2-y1)    a=y2-y1    b=x1-x2    */        a = y2 - y1;        b = x1 - x2;        /*    c=-ax1-by1    (y2-y1)x1+(x1-x2)y1+c=0    c=-(y2-y1)x1-(x1-x2)y1    */        c = -a * x1 - b * y1;    }    return [a, b, c];}