'''
【程序61】
题目：打印出杨辉三角形（要求打印出10行如下图）　　　
1.程序分析： 
'''

if __name__ == '__main__':
    a = []
    for i in range(10):
        a.append([])
        for j in range(10):
            a[i].append(0)
    for i in range(10):
        a[i][0] = 1
        a[i][i] = 1
    for i in range(2,10):
        for j in range(1,i):
            a[i][j] = a[i - 1][j-1] + a[i - 1][j]
    from sys import stdout
    for i in range(10):
        for j in range(i + 1):
            stdout.write(a[i][j])
            stdout.write(' ')
        print
        

'''
题目：画椭圆ellipse　　　
1.程序分析：
2.程序源代码：
'''
if __name__ == '__main__':
    from Tkinter import *
    x = 360
    y = 160
    top = y - 30
    bottom = y - 30
    
    canvas = Canvas(width = 400,height = 600,bg = 'white')
    for i in range(20):
        canvas.create_oval(250 - top,250 - bottom,250 + top,250 + bottom)
        top -= 5
        bottom += 5
    canvas.pack()
    mainloop()

'''
题目：利用ellipse and rectangle 画图。
1.程序分析：
2.程序源代码：
'''
if __name__ == '__main__':
    from Tkinter import *
    canvas = Canvas(width = 400,height = 600,bg = 'white')
    left = 20
    right = 50
    top = 50
    num = 15
    for i in range(num):
        canvas.create_oval(250 - right,250 - left,250 + right,250 + left)
        canvas.create_oval(250 - 20,250 - top,250 + 20,250 + top)
        canvas.create_rectangle(20 - 2 * i,20 - 2 * i,10 * (i + 2),10 * ( i + 2))
        right += 5
        left += 5
        top += 10

    canvas.pack()
    mainloop()
        

'''
【程序65】
题目：一个最优美的图案。　　　
1.程序分析：
2.程序源代码：
'''
import math
class PTS:
    def __init__(self):
        self.x = 0
        self.y = 0
points = []

def LineToDemo():
    from Tkinter import *
    screenx = 400
    screeny = 400
    canvas = Canvas(width = screenx,height = screeny,bg = 'white')

    AspectRatio = 0.85
    MAXPTS = 15
    h = screeny
    w = screenx
    xcenter = w / 2
    ycenter = h / 2
    radius = (h - 30) / (AspectRatio * 2) - 20
    step = 360 / MAXPTS
    angle = 0.0
    for i in range(MAXPTS):
        rads = angle * math.pi / 180.0
        p = PTS()
        p.x = xcenter + int(math.cos(rads) * radius)
        p.y = ycenter - int(math.sin(rads) * radius * AspectRatio)
        angle += step
        points.append(p)
    canvas.create_oval(xcenter - radius,ycenter - radius,
                       xcenter + radius,ycenter + radius)
    for i in range(MAXPTS):
        for j in range(i,MAXPTS):
            canvas.create_line(points[i].x,points[i].y,points[j].x,points[j].y)

    canvas.pack()
    mainloop()
if __name__ == '__main__':
    LineToDemo()

'''
【程序66】
题目：输入3个数a,b,c，按大小顺序输出。　　　
1.程序分析：利用指针方法。
2.程序源代码：
'''
if __name__ == '__main__':
    n1 = int(raw_input('n1 = :\n'))
    n2 = int(raw_input('n2 = :\n'))
    n3 = int(raw_input('n3 = :\n'))

    def swap(p1,p2):
        return p2,p1

    if n1 > n2 : n1,n2 = swap(n1,n2)
    if n1 > n3 : n1,n3 = swap(n1,n3)
    if n2 > n3 : n2,n3 = swap(n2,n3)

    print n1,n2,n3

'''
题目：输入数组，最大的与第一个元素交换，最小的与最后一个元素交换，输出数组。
1.程序分析：谭浩强的书中答案有问题。　　　　　　
2.程序源代码：
'''
def inp(numbers):
    for i in range(9):
        numbers.append(int(raw_input('input a number:\n')))
    numbers.append(int(raw_input('input a number:\n')))
p = 0
def max_min(array):
    max = min = 0
    for i in range(1,len(array) - 1):
        p = i
        if array[p] > array[max] : max = p
        elif array[p] < array[min] : min = p
    k = max
    l = min
    array[0],array[l] = array[l],array[0]
    array[9],array[k] = array[k],array[9]

def outp(numbers):
    for i  in range(len(numbers)):
        print numbers[i]

if __name__ == '__main__':
    array = []
    inp(array)
    max_min(array)
    outp(array)
    

'''
【程序68】
题目：有n个整数，使其前面各数顺序向后移m个位置，最后m个数变成最前面的m个数
1.程序分析：
2.程序源代码：
'''
if __name__ == '__main__':
    n = int(raw_input('the total number is:\n'))
    m = int(raw_input('back m:\n'))

    def move(array,n,m):
        array_end = array[n - 1]
        for i in range(n - 1,-1,- 1):
            array[i] = array[i - 1]
        array[0] = array_end
        m -= 1
        if m > 0:move(array,n,m)
        
    number = []
    for i in range(n):
        number.append(int(raw_input('input a number:\n')))
    print 'orignal number:',number

    move(number,n,m)

    print 'after moved:',number

'''
【程序69】
题目：有n个人围成一圈，顺序排号。从第一个人开始报数（从1到3报数），凡报到3的人退出
　　　圈子，问最后留下的是原来第几号的那位。
1. 程序分析：
2.程序源代码： 
'''
if __name__ == '__main__':
    nmax = 50
    n = int(raw_input('please input the total of numbers:'))
    num = []
    for i in range(n):
        num.append(i + 1)

    i = 0
    k = 0
    m = 0

    while m < n - 1:
        if num[i] != 0 : k += 1
        if k == 3:
            num[i] = 0
            k = 0
            m += 0
        i += 1
        if i == n : i = 0

    i = 0
    while num[i] == 0: i += 1
    print num[i]

'''
题目：写一个函数，求一个字符串的长度，在main函数中输入字符串，并输出其长度。　　　
1.程序分析：
2.程序源代码
就这样吧
'''
if __name__ == '__main__':
    s = raw_input('please input a string:\n')
    print 'the string has %d characters.' % len(s)