python课堂实验（6）(Python classroom experiment (6))

第6次实验

1、计算1000以内的所有完数个数和

n = 0
for i in range(1,1001):
    s = 1
    for j in range(2,i):
        if i%j == 0:
            s = s + j
    if s == i:
        n = n+i
print('1000以内共有{}个完数'.format(n))

2、区间素数和

def lsPrime(n):
    for i in range(2,n-1):
        if n%i==0:
            return False
        return True

m,n = eval(input('请输入整数m:')),eval (input('请输入整数n:'))
c = 0
for i in range(m,n+1):
    if IsPrime(i):
        c = c+i
print('范围在[{},{}的素数和为{}'.format(m,n,c))

3、

1)定义函数def f_write:用随机函数生成10行数据，每行数据个数3到8个不等，每个整数范围为[-50,50]。数据保存为data.txt

import random
random.seed(1000)
def f_write():
    a = open("data.txt",'w')
    for i in range(10):
        s = random.randint(3,9)
    for j in range(s):
        a.write(str(random.randint(-50,50)))
    if j == s-1:
        a.wrte('\n')
    else:
        a.write(',')
    a.close

2)定义函数def f_read(),用read函数求文件data.txt中全部数字的最大值，并输出

def f_read()
    max1 = 0   
    a = open("data.txt",'r')
    for i in range(10):
        str = f.readline()
        num = str.split('')
        for j in num:
            if int(j)>max1:
                max1 = int(j)
    print('数字最大值'，max1)
    f.close()

3)用readlines求每行数字和的最大值

def f_readlines():
    f = open('data.txt','r')
    maxn=0
    line = f.readlines()
    for str in line:
        num=str.split('')
        sum=0
        for j in num:
            sum=sum+int(j)
        if maxn<sum:
            maxn=sum
    print（"每行和最大值",maxn)

4、下载附件，每行有3个整数（有负数）。编写程序，读入所有数据，如果某行的三个整数能构成三角形则计算其面积，输出所有面积的最大值(保留两位小数）及三个边长的值。若三角形三边长分别为a,b,c，计算p=(a+b+c)/2，则该三角形的面积的平方=p*(p-a)*(p-b)*(p-c)。

f = open('整数.txt','r')
count=0
a,b,c,max= 0,0,0.0
for line in f:
    line=line.replace('\n','')
    d=line.split(',')
    if len(d)==3:
        x=eval(d[0])
        y=eval(d[1])
        z=eval(d[2])
        if x>0 and y>0 and z>0 and x+y>z and x+z>y and y+z>x:
             p=(x+y+z)/2
            s=(p*(p-x)*(p-y)*(p-z))**0.5
            if s>max:
                max=s
                a,b,c=x,y,z
f.close()

5、

f=open("阶乘.txt","w")
t=1
for i in range(1,101):
    t = t*i
    f.write('str(i)+"!="+str(t)+"\n")
f.close()
————————

Experiment 6

1. Calculate the sum of all completions within 1000

n = 0
for i in range(1,1001):
    s = 1
    for j in range(2,i):
        if i%j == 0:
            s = s + j
    if s == i:
        n = n+i
print('1000以内共有{}个完数'.format(n))

2. Interval prime sum

def lsPrime(n):
    for i in range(2,n-1):
        if n%i==0:
            return False
        return True

m,n = eval(input('请输入整数m:')),eval (input('请输入整数n:'))
c = 0
for i in range(m,n+1):
    if IsPrime(i):
        c = c+i
print('范围在[{},{}的素数和为{}'.format(m,n,c))

3、

1) Define function def f_ Write: generate 10 rows of data with random function, the number of data in each row ranges from 3 to 8, and the range of each integer is [- 50,50]. Save the data as data txt

import random
random.seed(1000)
def f_write():
    a = open("data.txt",'w')
    for i in range(10):
        s = random.randint(3,9)
    for j in range(s):
        a.write(str(random.randint(-50,50)))
    if j == s-1:
        a.wrte('\n')
    else:
        a.write(',')
    a.close

2) Define function def f_ Read(), use the read function to find the file data Txt, and output

def f_read()
    max1 = 0   
    a = open("data.txt",'r')
    for i in range(10):
        str = f.readline()
        num = str.split('')
        for j in num:
            if int(j)>max1:
                max1 = int(j)
    print('数字最大值'，max1)
    f.close()

3) Use readlines to find the maximum value of the sum of numbers in each line

def f_readlines():
    f = open('data.txt','r')
    maxn=0
    line = f.readlines()
    for str in line:
        num=str.split('')
        sum=0
        for j in num:
            sum=sum+int(j)
        if maxn<sum:
            maxn=sum
    print（"每行和最大值",maxn)

4. Download the attachment. There are 3 integers (negative numbers) in each line. Write a program to read all data. If three integers in a row can form a triangle, calculate its area, and output the maximum value of all areas (two decimal places) and the value of three side lengths. If the length of three sides of a triangle is a, B and C respectively, calculate P = (a + B + C) / 2, then the square of the area of the triangle = P * (P-A) * (P-B) * (P-C).

f = open('整数.txt','r')
count=0
a,b,c,max= 0,0,0.0
for line in f:
    line=line.replace('\n','')
    d=line.split(',')
    if len(d)==3:
        x=eval(d[0])
        y=eval(d[1])
        z=eval(d[2])
        if x>0 and y>0 and z>0 and x+y>z and x+z>y and y+z>x:
             p=(x+y+z)/2
            s=(p*(p-x)*(p-y)*(p-z))**0.5
            if s>max:
                max=s
                a,b,c=x,y,z
f.close()

5、

f=open("阶乘.txt","w")
t=1
for i in range(1,101):
    t = t*i
    f.write('str(i)+"!="+str(t)+"\n")
f.close()