習題4-2:此題不難,我採取最直接的辦法,暴力遍歷進行判斷,**如下:
def
do_squares
(h,v,n):
#h,v是乙個矩陣
deftest
(i,j,l):
_i = i;_j = j
while(_jif(h[_i][_j]==0):return
false
_j+=1
while(_iif(v[_i][_j]==0):return
false
_i+=1
while(_j>j):
if(h[_i][_j-1]==0):return
false
_j-=1
while(_i>i):
if(v[_i-1][_j]==0):return
false
_i-=1
return
true
count = [0]*(n-1)
for i in range(1,n-1):
for j in range(1,n-1):
for length in range(1,n-1):#長度從1-n-1
if(test(i,j,length)):count[length]+=1
for k in range(1,n-1):
if(count[k]!=0):print('number of suqare with length(%d) : %d'%(k,count[k]))
defsquares
(h,v,n):
h = [ [0]*(n+1) for i in range(n+1)]
v = [ [0]*(n+1) for j in range(n+1)]
for x in h:h[x[0]][x[1]] = 1
for y in v:v[y[0]][y[1]] = 1
do_squares(h,v,n+1)
squares([(1,1),(1,3),(2,1),(2,2),(2,3),(3,2),(4,2),(4,3)]
,[(1,1),(1,2),(2,2),(3,2),(2,3),(1,4),(2,4),(3,4)],4)
def cube(a,b):
x = [[a[0],a[5]],[a[1],a[4]],[a[2],a[3]]]
y = [[b[0],b[5]],[b[1],b[4]],[b[2],b[3]]]
for i in range(3):
x[i].sort();y[i].sort()
x.sort();y.sort()
print(x==y)
cube('grggrb','rggbgr')
def
convert
(x):
ans = ''
tmp = x.split('.')
for each in tmp:
tmp_ans = bin(int(each))[2:]
ans += '0'*(8-len(tmp_ans))+tmp_ans
return ans
defrecovert
(y):
ans = ''
for i in range(0,32,8):
ans += str(int(y[i:i+8],base = 2))+'.'
return ans[:-1]
defsolve
(ip):
net = convert(ip[0])
for each_ip in ip[1:]:
tmp = convert(each_ip)
for i in range(len(net)):
if(tmp[i]!=net[i]):net = net[:i];break
mask = '1'*len(net)+'0'*(32-len(net))
net += '0'*(32-len(net))
print('%s*********************%s'%(recovert(net),recovert(mask)))
solve(['194.85.160.183','194.85.160.177','194.85.160.178'])
def
do_raid
(d,s,b,type):
#b代表資料塊
check_result = 0
if type=='e'
else
1def
eor(x,check_pos):
ans = 0
count = 0
err_pos = 0
for i,each in enumerate(x):
if(each!='?'):ans ^= int(each,base = 2)
else:count+=1;err_pos = i
if(count>1):return
false,x
elif(count==1):
tmp = bin(ans^check_result)[2:]
x[err_pos] = '0'*(s-len(tmp))+tmp
return
true,x[0:check_pos]+x[check_pos+1:]#去掉校驗碼的部分
check_pos = 0
final_ans = ''
for i in range(0,len(b),d):
if(b[check_pos]=='?'):print('check illegal');return
test,tmp = eor(b[i:i+d],check_pos%d)
ifnot test:print('too many error');return
#磁碟資料損壞過多
check_pos += (d+1)
print(tmp)
final_ans += ''.join(tmp)
print(final_ans,hex(int(final_ans,2)))
do_raid(5,2,['00','01','10','11','?','01','10','11','10','?','01','11','01','10','?',
'11','10','?','11','01','11','11','11','00','11'],'e')
def
tired_students
(students):
n = len(students)
a = [students[i][0] for i in range(n)]
b = [students[i][1] for i in range(n)]
c = [students[i][2]-0.5
for i in range(n)]
print(a,b,c)
time = 1
sleeped = 0
initial_c = c[:]
tmp = [1]*n
for i in range(n):
if(c[i]>a[i]):sleeped += 1;tmp[i] = 0
print(sleeped,tmp)
while(sleeped !=0):
time += 1
tmp_sleeped = 0
for i,each in enumerate(c):#遍歷每乙個學生的情況
c[i] = (c[i]+1)%(a[i]+b[i])#獲取當前在週期裡面的位置
if(c[i]>a[i]):#到了睡覺時間
if(tmp[i] == 1):#上一刻處於聽課
if(2*sleeped > n):#滿足睡覺條件
tmp[i] = 0
tmp_sleeped += 1
else:
c[i] = 0
#在睡覺a[i]分鐘
elif(tmp[i]==0):#到了醒來的時間#上一刻處於睡覺狀態
tmp[i] = 1
tmp_sleeped -= 1
sleeped += tmp_sleeped
print('the %d分鐘: '%time,tmp,sleeped,c)#測試情況
if(initial_c == c and sleeped != 0):return -1
#不會有這個時刻
return time
def
flooded
(m,n,h,v):
h.sort()#對高度排序
num = m*n
v0 = v
v1 = 0
tmp_h = 0
final_h = 0
count = 0
last_h = 0
i = 0
while(i<100):
if(h[i] != last_h):
if(v0+v1+(num - i)*(h[i]-last_h)*100
< h[i]*num*100 ):
final_h = last_h;break
else:
v1 += (num - i)*(h[i]-last_h)*100
last_h = h[i]
i += 1
x = num - i
print(final_h,(v0+v1-100*num*last_h)/(100*num-x*num)+last_h,i/num)
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