问我的.slice()方法变异原始数组(TypeScript)

EN

class ChapterOne {
    
    // Gauss Jordan Elimination
    // Notes: Only solve system of linear equation with one solution
    static gaussJordanElim( linsys : number[][] ) {
        const numOfEquation = linsys.length
        const numOfUnknown = linsys[0].length - 1
        if (numOfUnknown > numOfEquation) return 'This System of Linear Equation either have no solution or have infinite solutions'
        
        // I slice it here.
        const input = linsys.slice()
        const length = input.length
        // pointer = i, row to operate = j, column to operate = k
        for (let i = 0; i < length; i += 1) {
            if (input[i][i] === 0) return 'Mathematical Error! Cannot divide by zero'
            for (let j = 0; j < length; j += 1) {
                if (i !== j) {
                    const ratio = input[j][i] / input[i][i]
                    for (let k = 0; k < length + 1; k += 1) {
                        input[j][k] = input[j][k] - ratio * input[i][k]
                    }
                }
            }
        }
        // I Checked it here
        console.log(input)
        console.log(linsys)

        const output = input.map((row, pointer) => row[length] / row[pointer])
        return output
    }
}