def solveDQ(state, base_cases, get_sub_problems, merge):
for condition, result in base_cases:
if condition(state):
return result(state)
sub_problems = get_sub_problems(state)
sub_results = [
solveDQ(sub_problem, base_cases, get_sub_problems, merge)
for sub_problem in sub_problems
]
result = merge(sub_results)
return result
def binary_search_first_high(l, r, condition):
def get_sub_problems(state):
l, r = state
mid = (l + r) // 2
if condition(mid):
return [(l, mid)]
else:
return [(mid + 1, r)]
state = (l, r)
base_cases = [(lambda s: s[0] == s[1], lambda s: s[0])]
merge = lambda sub_results: sub_results[0]
return solveDQ(
state,
base_cases,
get_sub_problems,
merge,
)
if __name__ == "__main__":
n = int(input())
def isValid(n):
def condition(mid):
taken = 0
nonlocal n
base = n
while(base):
portion = base if base <= mid else mid
taken += portion
base -= portion
base -= base // 10
return 2 * taken >= n
return condition
print(binary_search_first_high(1, n, isValid(n)))#include <bits/stdc++.h>
#define F first
#define S second
#define endl "\n";
#define shekoo ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
using namespace std;
typedef long long ll;
typedef pair<int, int> pi;
typedef pair<ll, ll> pll;
const ll mod = 1e9+7;
bool check(ll mid, ll cur){
ll sum = 0;
ll n = cur;
while(cur > 0){
ll have = min(cur, mid);
cur -= have;
sum += have;
cur -= (cur/10);
}
return (2*sum >= n);
}
int main() {
shekoo
ll n; cin >> n;
ll st = 1, en = n, ans = 0;
while(st <= en){
ll mid = (st+en)/2;
if(check(mid, n)){
ans = mid;
en = mid-1;
}
else{
st = mid+1;
}
}
cout << ans;
return 0;
} 1302. Deepest Leaves Sum | 1209. Remove All Adjacent Duplicates in String II |
994. Rotting Oranges | 983. Minimum Cost For Tickets |
973. K Closest Points to Origin | 969. Pancake Sorting |
967. Numbers With Same Consecutive Differences | 957. Prison Cells After N Days |
946. Validate Stack Sequences | 921. Minimum Add to Make Parentheses Valid |
881. Boats to Save People | 497. Random Point in Non-overlapping Rectangles |
528. Random Pick with Weight | 470. Implement Rand10() Using Rand7() |
866. Prime Palindrome | 1516A - Tit for Tat |
622. Design Circular Queue | 814. Binary Tree Pruning |
791. Custom Sort String | 787. Cheapest Flights Within K Stops |
779. K-th Symbol in Grammar | 701. Insert into a Binary Search Tree |
429. N-ary Tree Level Order Traversal | 739. Daily Temperatures |
647. Palindromic Substrings | 583. Delete Operation for Two Strings |
518. Coin Change 2 | 516. Longest Palindromic Subsequence |
468. Validate IP Address | 450. Delete Node in a BST |