python——加权平均问题，保留一位小数，且不四舍五入

result = 0
arr = input("")
score_weight = [int(n) for n in arr.split()]
for i in range(1, len(score_weight)+1):result += i*score_weight[i-1]
result_final = int((result/sum(score_weight))*10)/10
print(result_final)