Submission #145542

#	Time	Username	Problem	Language	Result	Execution time	Memory
145542		Ok_google	Ljetopica (COI19_ljetopica)	C++17	8 / 100	3 ms	376 KiB

ljetopica

#include<bits/stdc++.h>
#define pb push_back
#define fr first
#define sc second
#define ll long long
using namespace std;
 
const int mnx = 1e6 + 5;
const int mod = 1e9 + 7;

ll n, k;
string s;
string a, b;

bool gon(string a, string b){
	if(a.size() > b.size()) return 1;
	if(a.size() < b.size()) return 0;
	
	for(int i = 1; i <= a.size(); i++){
		if(a[i] > b[i]) return 1;
		if(a[i] < b[i]) return 0;
	}
	return 1;
}

string x, y;

string mkd(string a, string b){
	string c;
	
	for(int i = 0; i <= a.size(); i++){
		c += '0';
	}
	
	for(int i = a.size() - 1; i >= 0; i--){
		c[i + 1] = c[i + 1] + a[i] + b[i] - '0' - '0';
		if(c[i + 1] >= '2'){
			c[i + 1] -= 2;
			c[i] += 1;
		}
	}
	
	return c;
}

ll asd(string s){
	ll k = 1;
	ll sum = 0;
	
	for(int i = s.size() - 1; i >= 0; i--){
		if(s[i] == '1'){
			sum += k;
			sum %= mod;
		}
		k *= 2;
		k %= mod;
	}
	
	return sum;
}

int main(){
	cin >> n >> k;
	cin >> s;
	cin >> a >> b;
	
	if(k != 0){
		cout << 0 << '\n';
		return 0;
	}
	
	x = "1";
	y = "1";
	
	for(int i = 0; i < s.size(); i++){
		x += (s[i] == 'R') + '0';
		y += (s[i] == 'L') + '0';
	}
	
	bool ok = 0;
	bool ko = 0;
	
	if(gon(b, x) && gon(x, a)){
		ok = 1;
	}
	
	if(gon(b, y) && gon(y, a)){
		ko = 1;
	}
	
	string f, z;
	
	if(ok && ko){
		z = mkd(x, y);
	}
	
	if(ok && !ko){
		z = x;
	}
	
	if(!ok && ko){
		z = y;
	}
	
	cout << asd(z) << '\n';
    return 0;
}

Compilation message (stderr)

ljetopica.cpp: In function 'bool gon(std::__cxx11::string, std::__cxx11::string)':
ljetopica.cpp:19:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 1; i <= a.size(); i++){
                 ~~^~~~~~~~~~~
ljetopica.cpp: In function 'std::__cxx11::string mkd(std::__cxx11::string, std::__cxx11::string)':
ljetopica.cpp:31:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i <= a.size(); i++){
                 ~~^~~~~~~~~~~
ljetopica.cpp: In function 'int main()':
ljetopica.cpp:75:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < s.size(); i++){
                 ~~^~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 0 / 14
• Subtask 3: 0 / 17
• Subtask 4: 0 / 61