## 求曲边图形的面积
# for
n=1000
width = 2*math.pi/n;
x=[]
y=[]
for i in range(n):
    x.append(i*width)
for i in x:
    y.append(abs(math.sin(i)))
ans=sum(y)*width
print(ans)
# 列表推导式
s=[abs(math.sin(i*width))*width for i in range(n)]
print(sum(s))