Submission #101685

#	Time	Username	Problem	Language	Result	Execution time	Memory
101685		jamielim	Tracks in the Snow (BOI13_tracks)	C++14	100 / 100	999 ms	110692 KiB

tracks

#include <bits/stdc++.h>
using namespace std;
int main() {
    int h,w;
	scanf("%d%d",&h,&w);
	char grid[h+5][w+5];
	for(int i=0;i<h;i++)scanf("%s",grid[i]);
	deque<pair<int,int> > q;
	q.push_back(make_pair(0,0));
	int dx[]={0,0,1,-1},dy[]={1,-1,0,0};
	int dist[h][w];
	for(int i=0;i<h;i++){
		for(int j=0;j<w;j++)dist[i][j]=1000000010;
	}
	dist[0][0]=1;
	while(!q.empty()){
		pair<int,int> cur=q.front();q.pop_front();
		for(int i=0;i<4;i++){
			int nx=cur.first+dx[i],ny=cur.second+dy[i];
			if(0<=nx&&nx<h&&0<=ny&&ny<w&&grid[nx][ny]!='.'){
				if(grid[nx][ny]==grid[cur.first][cur.second]){
					if(dist[nx][ny]>dist[cur.first][cur.second]){
						dist[nx][ny]=dist[cur.first][cur.second];
						q.push_front(make_pair(nx,ny));
					}
				}else{
					if(dist[nx][ny]>dist[cur.first][cur.second]+1){
						dist[nx][ny]=dist[cur.first][cur.second]+1;
						q.push_back(make_pair(nx,ny));
					}
				}
			}
		}
	}
	int ans=1;
	for(int i=0;i<h;i++){
		for(int j=0;j<w;j++){
			if(dist[i][j]<1000000010)ans=max(ans,dist[i][j]);
		}
	}
	printf("%d",ans);
}

Compilation message (stderr)

tracks.cpp: In function 'int main()':
tracks.cpp:5:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&h,&w);
  ~~~~~^~~~~~~~~~~~~~
tracks.cpp:7:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i=0;i<h;i++)scanf("%s",grid[i]);
                      ~~~~~^~~~~~~~~~~~~~

• Subtask 1: 30 / 30
• Subtask 2: 70 / 70