练习1:求一个数字的阶乘 function getJieCheng(num) { var result = 1; for (var i = 1; i <= num; i++) { result *= i; } return result; } console.log(getJieCheng(6)); //1*2*3*4*5*6 练习2:求一个数字的阶乘和 ps: 5的阶乘和:即5的阶乘+4的阶乘+3的阶乘+2的阶乘+1的阶乘 function getJieChengSum(num) { var…