Submission #372225

#	Time	Username	Problem	Language	Result	Execution time	Memory
372225		cpp219	Painting Squares (IOI20_squares)	C++14	0 / 100	1 ms	412 KiB

squares

#pragma GCC target ("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")

#include<bits/stdc++.h>
#define ll int
#define ld long double
#define fs first
#define sc second
using namespace std;
typedef pair<ll,ll> LL;
const ll N = 2e3 + 9;
const ll mod = 1e9 + 7;

vector<ll> g[N];
deque<ll> ans;
ll b[N],pow2[N],p1,p2;

void process(){
    p1 = p2 = 0;
    for (ll i = 0;i < 9;i++) p1 += pow2[9 - i - 1]*b[i];
    for (ll i = 1;i <= 9;i++) p2 += pow2[9 - i]*b[i];
    g[p1].push_back(p2);
}

void f(ll i){
    if (i > 9){
       process(); return;
    }
    b[i] = 1; f(i + 1);
    b[i] = 0; f(i + 1);
}

void dfs(ll u){
    while(g[u].size()){
        ll v = g[u].back(); g[u].pop_back();
        dfs(v);
    }
    ans.push_back(u%2);
}

void Init(ll n){
    pow2[0] = 1;
    for (ll i = 1;i <= 10;i++) pow2[i] = pow2[i - 1]*2; f(0);
    dfs(0); reverse(ans.begin(),ans.end());
    for (ll i = 0;i < 8;i++) ans.push_front(0);
    while(ans.size() > n) ans.pop_back();
}

vector<int> paint(int n) {
	if (ans.empty()) Init(n);
	vector<int> a(n + 1);
	a[n] = 10;
	for (int i = 0; i < n; i++) a[i] = ans[i];
	return a;
}

vector<int> now;
int find_location(int n, vector<int> c) {
	if (ans.empty()) Init(n);
	/*for (int i = 0; i < 10; i++) cout << c[i] <<" ";cout << endl;
	for (int i = 0; i < 10; i++) cout << need[i] <<" ";cout << endl;*/
	for (int i = 0; i < n; i++) {
		now.clear();
		for (int j = 0; j < 10; j++) {
			if (i + j >= n) now.push_back(-1);
			else now.push_back(ans[i + j]);
		}
		if (now == c) return i;
	}
	assert(false);
}
/*
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    #define task "tst"
    if (fopen(task".INP","r")){
        freopen(task".INP","r",stdin);
        //freopen(task".OUT","w",stdout);
    }
    cin>>n; paint(n); /// 00000000001000000001
    v.push_back(0); v.push_back(1);
    while(v.size() < 10) v.push_back(-1);
    cout<<find_location(n,v);
}
*/

Compilation message (stderr)

squares.cpp:2: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    2 | #pragma GCC optimization ("O3")
      | 
squares.cpp:3: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    3 | #pragma GCC optimization ("unroll-loops")
      | 
squares.cpp: In function 'void Init(int)':
squares.cpp:44:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   44 |     for (ll i = 1;i <= 10;i++) pow2[i] = pow2[i - 1]*2; f(0);
      |     ^~~
squares.cpp:44:57: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   44 |     for (ll i = 1;i <= 10;i++) pow2[i] = pow2[i - 1]*2; f(0);
      |                                                         ^
squares.cpp:47:22: warning: comparison of integer expressions of different signedness: 'std::deque<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   47 |     while(ans.size() > n) ans.pop_back();
      |           ~~~~~~~~~~~^~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 15
• Subtask 3: 0 / 20
• Subtask 4: 0 / 55