Go: package main

import (
	"bufio"
	"os"
	"strconv"
	"fmt"
)

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	for scanner.Scan() {
		a, _ := strconv.ParseFloat(scanner.Text(), 64)
			t := a/9.8
			x := t*t*4.9
			ans := (x+5)/5+1
			fmt.Printf("%d\n", int(ans))
	}
}

Python: from math import ceil

while True:
    try:
        v = input()
    except:
        break
    v = float(v)
    print(ceil(v * v / 98 + 1))

Python: while True:
    try:
        v = float(input())
        h = (v / 9.8) * (v / 9.8) * 4.9
        N = (h + 5) / 5
        N1 = (h + 5) // 5
        if (N - N1 > 0):
            N1 += 1
        print(int(N1))
    except EOFError:
        break

Python: while(1):
    try:
        n=float(input())
        t=n/9.8
        y=4.9*t**2
        N=(y+5)//5
        print(N+1)
    except EOFError:
        break

Python: try:
    while 1:
        y = 4.9 * (float(input()) / 9.8) ** 2
        N = 1
        while N * 5 - 5 < y:
            N += 1
        print(N)
except:
    pass

Python: while True:
    try:
        v = float(input())
    except:
        break
    print(int(v ** 2 / 98 + 1.5))

Python: while True :
    try :
        min_y = float(input())
        t = min_y / 9.8
        y = 4.9 * (t ** 2)
        if y % 5 > 0 : N = int(y // 5 + 2)
        else         : N = int(y // 5 + 1)
        print(N)
    except : break

Python: # Aizu Problem 0024: Physical Experiments
#
import sys, math, os

# read input:
PYDEV = os.environ.get('PYDEV')
if PYDEV=="True":
    sys.stdin = open("sample-input.txt", "rt")


for line in sys.stdin:
    v_crack = float(line)
    y = v_crack**2 * 4.9 / 9.8**2
    N = y / 5 + 1
    print(math.ceil(N))

Python: import math
while True:
    try:
        v = float(input())
    except:
        break
    print(math.ceil(4.9 * (v / 9.8) ** 2 / 5) + 1)

Python: while True:
    flag=0
    v=float(input())
    t=v/9.8
    y=4.9*t**2
    N=0
    while y>5*(N-1):
        N +=1
    print(N)
    flag +=1
    if flag==50:break

Python: import math
h=lambda n:math.sqrt((5*n-5)/4.9)*9.8

while True:
    try:v=float(input())
    except:break
    n=1
    while True:
        if h(n)>v:break
        n+=1
    print(n)

Python: while True:
    try:
        v = float(input())
    except:
        break
    t = v / 9.8
    y = 4.9 * pow(t, 2)
    N = (y + 5) / 5
    print(round(N))

Python: v=int(input())
f=2
g=9.8
while True:
    F=f*5-5
    if sqrt(2*g*F)>=v:
        print(f)
        break
    f+=1

Python: from math import ceil

while True:
    v = input()
    if not v:
        break
    v = float(v)
    print(ceil(v * v / 98 + 1))

Python: import math,sys
for e in sys.stdin:
 g=9.8;print(math.ceil((g/2*(float(e)/g)**2+5)/5))

Python: from math import ceil
while(1):
	try:
		a = float(input())
		t = a/9.8
		y = 4.9*t**2
		n = ceil((y+5)/5)
		print(n)
	except EOFError:
		break

Python: # AOJ 0024 Physical Experiments
# Python3 2018.6.14 bal4u

while True:
    try:
        v = float(input())
        print((int)(v**2 / 19.6) // 5 + 2)
    except EOFError:
        break

Python: import sys
import math

for line in sys.stdin:
    x = float(line)

    for i in range(500):
        y = i * 5
        if math.sqrt(y / 4.9) * 9.8 >= x:
            print(i + 1)
            break

Python: while True:
    try:
        v = float(input())
        print((int)(v**2 / 19.6) // 5+2)
    except:
        break

Python: import math
while True:
    try:
        v=float(input())
        print(int(math.ceil(v**2/98+1)))
    except:
        break

Python: import math
while True:
    try:
        v = float(input())
    except:
        break
    t = v / 9.8
    y = 4.9 * pow(t, 2)
    N = (y + 5) / 5
    print(math.ceil(N))

Python: import sys
from math import ceil

for line in sys.stdin:
    needh = (float(line) **2 )/ 2 / 9.8
    print(ceil(needh/5)+1)

Python: while True:
    try:
        x=float(input())
        cnt=1
        while True:
            y=cnt*5-5
            t=(y/4.9)**0.5
            v=t*9.8
            if x<=v:
                print(cnt)
                break
            else: cnt+=1

    except:
        break

Python: import sys
import math
v=[]
for line in sys.stdin:
    v.append(float(line.rstrip()))
for i in range(len(v)):
    print(math.ceil(v[i]**2/98+1))

Python: import sys
import math
while(True):
    try:
        v=float(input())
        t=v/9.8
        y=4.9*t**2
        N=math.ceil((y+5)/5)
        print(N)
    except EOFError:
        sys.exit()

Python: while True:
    try:
        v = float(input())
    except:
        break
    
    y = (v/9.8) ** 2 * 4.9
    
    f = int(y/5)
    if y > f * 5:
        f += 1
    
    print(f+1)

Python: import sys
import math

def datasets():
    for line in sys.stdin:
        yield float(line)

def proc(fallspd):
    t = fallspd / 9.8
    y = 4.9 * t * t
    return math.ceil((y + 5.0) / 5.0)

if __name__ == '__main__':
    for d in datasets():
        print(proc(d))

Python: import math
import sys

def speed(floor):
    N = 5 * floor - 5
    time = math.sqrt(N/4.9)
    return (9.8 * time)

for s in sys.stdin:
    brkSpd = float(s)

    floor = 1

    while brkSpd > speed(floor):
        floor = floor + 1

    print(floor)

Python: import math

m = float(input())
t = m / 9.8
y = 4.9 * t * t
n = math.ceil(y / 5)
print(int(n + 1))

Python: import sys
import math
v=[]
for line in sys.stdin:
    v.append(float(line.strip()))
for i in range(len(v)):
    print(math.ceil(v[i]**2/98+1))

Python: import math

while True:
  try:
    v_i = float(input())
  except EOFError:
    break
  t = v_i / 9.8
  y = 4.9 * t**2
  flr = (y + 5) // 5 + 1
  print(int(flr))

Python: import math
while True:
    try:
        v = float(input())
        t = v / 9.8
        y = 4.9 * (t**2)
        N = y  / 5 + 1
        print(math.ceil(N))
    except EOFError:
        break

Python: import math
while True:
  try:
    v = float(input())
    t = v / 9.8
    y = 4.9 * t ** 2
    print(math.ceil(y / 5 + 1))
  except EOFError:
    break

Python: import math

while True:
    try:
        l=float(input())
    except:
        break

    y=4.9*(l/9.8)**2/5
    print(math.ceil(y)+1)

Python: import math,sys
for e in sys.stdin:print(int(float(input())**2/98+2))

Python: import sys
import math

g = 9.8

for i in sys.stdin:
    vd = float(i)
    N = int(math.ceil((vd**2 / (10 * g)) + 1))
    print(N)

Python: import math
while True:
    try:
        mv= float(input())
    except:
        break
    print(math.ceil((4.9*(mv/9.8)**2+5)/5))

Python: import sys
import math

g = 9.8

for i in sys.stdin:
    try:
        vd = float(i)
        N = int(math.ceil((vd**2 / (10 * g)) + 1))
        print(N)
    except:
        break

Python: from bisect import *
n = 1
max_v = 0
v_map = [0.0] * 500
while max_v < 200:
    h = 5 * n - 5
    t = (h / 4.9)**0.5
    v_map[n - 1] = 9.8 * t
    #print(n,h,t,v_map[n-1])
    max_v = max(v_map)
    n += 1

while True:
    try:
        x = float(input())
        print(bisect(v_map, x) + 1)
    except EOFError:
        break

Python: import math

while True:
  try:
    V = float(input())
    for n in range(1, 1000):
      height = 5 * n - 5
      t = math.sqrt( height/4.9 ) 
      v = 9.8 * t
      if v >= V:
        break
    print(n)
  except:
    break

Python: import sys
from math import ceil

for s in sys.stdin:
    t = float(s) / 9.8
    y = 4.9 * t * t
    print(ceil(y / 5) + 1)

Python: import math
while 1:
	try: print(math.ceil((math.ceil(4.9*(float(input())/9.8)**2)+5)/5))
	except: break

Python: import math
import sys
[print(math.ceil(float(e) ** 2 / 98) + 1) for e in sys.stdin]