Gidhub BE Developer

[BOJ] 14502. 연구소

2018-10-16
goodGid

Problem

Problem URL : 연구소

[1] Answer Code (18. 10. 16)

#include<iostream>
#include<vector>
#include<algorithm>
#include<queue>
#define p pair<int,int>
using namespace std;

// 동서남북
int dx[] = {0,0,1,-1};
int dy[] = {1,-1,0,0};

int n,m;
int map[8][8];
int ans;

vector<p> virus;
vector<p> list;

bool inRange(int x, int y){
if( x < 0 || x >= n || y < 0 || y >= m)
return false;
return true;
}

int cal(){
int v[8][8] = {0,};
queue<p> q;

for(int i=0; i<n; i++){
for(int j=0; j<m; j++){
v[i][j] = map[i][j];
}
}

for(int i=0; i<virus.size(); i++){
q.push(p(virus[i].first, virus[i].second));
}

while (! q.empty()) {
int x = q.front().first;
int y= q.front().second;
q.pop();

for(int i=0; i<4; i++){
int nx = x + dx[i];
int ny = y + dy[i];

if(! inRange(nx, ny)) continue;
if(v[nx][ny] == 2) continue;

if(map[nx][ny] == 1 || map[nx][ny] == 2){
v[nx][ny] = 1;
continue;
}
else if(map[nx][ny] == 0 && v[nx][ny] == 0 ){
v[nx][ny] = 2;
q.push(p(nx,ny));
}
}
}

int cnt = 0;
for(int i=0; i<n; i++){
for(int j=0; j<m; j++){
if(v[i][j] == 0)
cnt ++;
}
}

return cnt;
}

void dfs(int idx, int p_cnt){ // p_cnt is pick count
if(p_cnt == 3){
int res = cal();
ans = ans < res ? res : ans;
return ;
}
int size = (int)list.size();

for(int i=idx; i<size; i++){
int x = list[i].first;
int y = list[i].second;
map[x][y] = 1;
dfs(i+1,p_cnt+1);
map[x][y] = 0;
}
}

int main(){
ios::sync_with_stdio(0);
cin.tie(0);

ans = -1;

cin >> n >> m;
for(int i=0; i<n; i++){
for(int j=0; j<m; j++){
cin >> map[i][j];
if(map[i][j] == 0)
list.push_back(p(i,j));
else if(map[i][j] == 2)
virus.push_back(p(i,j));
}
}

dfs(0,0);

cout << ans << endl;
return 0;
}

Review

• 삼성 역량 테스트 기출 문제

• DFS + BFS