1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
|
#include <algorithm>
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
using vpii = vector<pii>;
using vi = vector<int>;
using vll = vector<long long>;
using mpii = map<int, int>;
using mpll = map<ll, ll>;
using db = long double;
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define lb lower_bound
#define ub upper_bound
#define make_unique(x) \
sort(all((x))); \
(x).resize(unique(all((x))) - (x).begin())
#define ceil(a, b) ((a) + (b)-1) / (b)
const int mod = (int)1e9 + 7;
const db pi = acos((db)-1);
const int dx[4]{1, 0, -1, 0};
const int dy[4]{0, 1, 0, -1};
#ifdef LOCAL
#include "debug.h"
#else
#define dbg(...) 42
#endif
/* stuff you should look for:
---------------------------
* special cases (n=1?)
* int overflow, array bounds
* do smth instead of nothing and stay organized
* WRITE STUFF DOWN
* DON'T GET STUCK ON ONE APPROACH
*/
bool isChip(vi v) {
v.resize(unique(all(v)) - v.begin());
int n = v.size();
if (n == 2) {
return true;
} else if (n == 1 && v[0] == 1) {
return true;
} else if (n == 3 && v[0] == 0 && v[1] == 1 && v[2] == 0) {
return true;
} else {
return false;
}
}
int rfind(vi &v) {
int n = v.size();
for (int i = n - 1; i >= 0; --i) {
if (v[i] == 1) {
return i;
}
}
return -1;
}
int helper(vi &v, int idx) {
int n = v.size();
for (int i = idx; i >= 0; --i) {
if (v[i] == 0) {
return i;
}
}
return -1;
}
void solve() {
int n;
cin >> n;
vi v(n);
for (auto &x : v) {
cin >> x;
}
int cnt = 0;
while (!isChip(v)) {
auto last_one = rfind(v);
auto first_zero_before_last_one = helper(v, last_one);
swap(v[last_one], v[first_zero_before_last_one]);
cnt++;
}
cout << cnt << '\n';
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int tt;
cin >> tt;
while (tt--) {
solve();
}
}
|
