CSES - Datatähti 2016 alku - Results
Submission details
Task:Tontti
Sender:felixbade
Submission time:2015-10-11 15:47:36 +0300
Language:Python3
Status:READY
Result:14
Feedback
groupverdictscore
#1ACCEPTED14
#20
#30
Test results
testverdicttimegroup
#1ACCEPTED0.09 s1details
#2ACCEPTED0.08 s1details
#3ACCEPTED0.09 s1details
#4ACCEPTED0.09 s1details
#5ACCEPTED0.08 s1details
#6--2details
#7--2details
#8--2details
#9--2details
#10--2details
#11--3details
#12--3details
#13--3details
#14--3details
#15--3details

Code

import math
from array import array

# Parse input
line = input().split()
height = int(line[0])
width = int(line[1])
desired_trees = int(line[2])

field = []
for y in range(height):
    line = input()
    field.extend([x == '*' for x in line])

# Create index
index = []
for i in range(width*height):
    this = 0
    y, x = divmod(i, width)
    if field[i]:
        this = 1
    if y > 0:
        this += index[i-width]
    if x > 0:
        this += index[i-1]
    if y > 0 and x > 0:
        this -= index[i-width-1]
    index.append(this)
#index = array('I', index) # use array instead of list for sake of speed

# Calculate
def trees_in(x1, y1, size):
    x2 = x1 + size - 1
    y2 = y1 + size - 1
    if x1 == 0 and y1 == 0:
        return index[y2*width + x2]
    elif x1 == 0:
        return index[y2*width + x2] - index[(y1-1)*width + x2]
    elif y1 == 0:
        return index[y2*width + x2] - index[y2*width + (x1-1)]
    else:
        return (index[y2*width + x2] - index[(y1-1)*width + x2] -
                index[y2*width + (x1-1)] + index[(y1-1)*width + (x1-1)])

options = 0
min_min_size = math.ceil(math.sqrt(desired_trees))
last_min_sizes = [0]*width
for y in range(height):
    min_size = min_min_size
    for x in range(width):
        max_size = min(height-y, width-x)
        a = max(min_size, last_min_sizes[x])
        for size in range(a, max_size+1):
            trees = trees_in(x, y, size)
            if trees == desired_trees:
                options += 1
            elif trees > desired_trees:
                # bigger area can't have less trees
                break
            else:
                min_size = size - 1
        last_min_sizes[x] = min_size

print(options)

Test details

Test 1

Group: 1

Verdict: ACCEPTED

input
10 10 1
......*...
.......*..
*..*....*.
*....*....
...

correct output
94

user output
94

Test 2

Group: 1

Verdict: ACCEPTED

input
10 10 5
**********
**********
**********
**********
...

correct output
0

user output
0

Test 3

Group: 1

Verdict: ACCEPTED

input
10 10 10
**...*...*
*..*.**.*.
...**.*..*
*...**.*..
...

correct output
4

user output
4

Test 4

Group: 1

Verdict: ACCEPTED

input
10 10 5
****......
*.*.**..**
....*.*..*
...*.***..
...

correct output
16

user output
16

Test 5

Group: 1

Verdict: ACCEPTED

input
10 10 2
**.***..*.
...*.*....
.***.*...*
***.***..*
...

correct output
30

user output
30

Test 6

Group: 2

Verdict:

input
500 500 1
.................................

correct output
9552040

user output
(empty)

Test 7

Group: 2

Verdict:

input
500 500 5
.................................

correct output
1536063

user output
(empty)

Test 8

Group: 2

Verdict:

input
500 500 25000
**...*...**..*.*..*.**.*..*.*....

correct output
288

user output
(empty)

Test 9

Group: 2

Verdict:

input
500 500 12500
**.**.*..*...*.**...*.***........

correct output
786

user output
(empty)

Test 10

Group: 2

Verdict:

input
500 500 5000
.*.*.**..*.*.**.**..*..**...*....

correct output
1763

user output
(empty)

Test 11

Group: 3

Verdict:

input
2000 2000 1
.................................

correct output
489611392

user output
(empty)

Test 12

Group: 3

Verdict:

input
2000 2000 5
.................................

correct output
120725884

user output
(empty)

Test 13

Group: 3

Verdict:

input
2000 2000 400000
..*..**.**.**.*.***...**.*..**...

correct output
1849

user output
(empty)

Test 14

Group: 3

Verdict:

input
2000 2000 200000
***.*....*.*..*....**..*..*.*....

correct output
2665

user output
(empty)

Test 15

Group: 3

Verdict:

input
2000 2000 80000
**.**...*.***.**....**.*....*....

correct output
5587

user output
(empty)