#include<bits/stdc++.h>
using namespace std;
int main()
{
auto a = unordered_set<uint32_t>();
auto b = unordered_set<uint32_t>();
auto walked = unordered_set<uint32_t>();
uint32_t cnt = 0, target;
cin >> target;
if (target == 1) return cout << 0, 0;
b.insert(1);
walked.insert(0);
while (b.size() != 0)
{
a.swap(b);
cnt++;
b.clear();
for (auto val : a)
{
walked.insert(val);
uint32_t opResult;
if (!__builtin_umul_overflow(val, val, &opResult))
{
if (opResult == target) return cout << cnt, 0;
if (walked.find(opResult) == walked.end()) b.insert(opResult);
}
opResult = val + 1;
if (opResult == target) return cout << cnt, 0;
if (walked.find(opResult) == walked.end()) b.insert(opResult);
opResult = val - 1;
if (opResult == target) return cout << cnt, 0;
if (walked.find(opResult) == walked.end()) b.insert(opResult);
}
}
return 0;
}
#include<bits/stdc++.h>
using namespace std;
void dfs(uint32_t val, uint32_t step, uint32_t &ans)
{
if (step >= ans) return;
uint32_t down = sqrt((double)val);
if (down == 1)
ans = min(step + val - 1, ans);
else
dfs(down, step + 1 + (val - (down * down)), ans);
uint32_t up = down + 1;
uint32_t mulRes;
if (__builtin_umul_overflow(up, up, &mulRes)) return;
dfs(up, step + 1 + (mulRes - val), ans);
}
int main()
{
uint32_t target, ans = UINT32_MAX;
cin >> target;
if (target == 1) return cout << 0, 0;
dfs(target, 0, ans);
cout << ans;
return 0;
}
