Submission #156447

#	Time	Username	Problem	Language	Result	Execution time	Memory
156447		liwi	Tower Defense (CEOI19_towerdefense)	C++11	100 / 100	5 ms	424 KiB

towerdefense

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;

#define scan(x) do{while((x=getchar())<'0'); for(x-='0'; '0'<=(_=getchar()); x=(x<<3)+(x<<1)+_-'0');}while(0)
char _;
#define complete_unique(a) a.erase(unique(a.begin(),a.end()),a.end())
#define all(a) a.begin(),a.end()
#define println printf("\n");
#define readln(x) getline(cin,x);
#define pb push_back
#define endl "\n"
#define INT_INF 0x3f3f3f3f
#define LL_INF 0x3f3f3f3f3f3f3f3f
#define MOD 1000000007
#define MOD2 1494318097
#define SEED 131
#define mp make_pair
#define fastio cin.tie(0); cin.sync_with_stdio(0);

typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;
typedef unordered_map<int,int> umii;
typedef pair<int,int> pii;
typedef pair<double,double> pdd;
typedef pair<ll,ll> pll;
typedef pair<int,pii> triple;
typedef int8_t byte;

mt19937 g1(time(0));

int randint(int a, int b){return uniform_int_distribution<int>(a, b)(g1);}
ll randlong(ll a,ll b){return uniform_int_distribution<long long>(a, b)(g1);}

ll gcd(ll a, ll b){return b == 0 ? a : gcd(b, a % b);}
ll lcm(ll a, ll b){return a*b/gcd(a,b);}
ll fpow(ll  b, ll exp, ll mod){if(exp == 0) return 1;ll t = fpow(b,exp/2,mod);if(exp&1) return t*t%mod*b%mod;return t*t%mod;}
ll divmod(ll i, ll j, ll mod){i%=mod,j%=mod;return i*fpow(j,mod-2,mod)%mod;}

int sx,sy,tx,ty,d;
vector<pii> res;

int main(){
	scanf("%d %d %d %d %d",&sx,&sy,&tx,&ty,&d);
	if(abs(sx-tx)+abs(sy-ty) > d) return 0*printf("impossible\n");
	if((abs(sx-tx)+abs(sy-ty))%2 != d%2) return 0*printf("impossible\n");
	int rem = d-abs(sx-tx)-abs(sy-ty);
	if(rem > 10000) return 0*printf("impossible\n");
	if(abs(sx-tx)+abs(sy-ty) == 1){
		if(d != 1) return 0*printf("impossible\n");
		return 0*printf("0\n");
	}else if(abs(sx-tx) == 1 && abs(sy-ty) == 1){
		if(d == 4) return 0*printf("impossible\n");
		rem-=2;
	}
	if(sx == tx){
		for(int i=0; i<rem/2; i++){
			res.pb(mp(sx-i,sy+(sy>ty?-1:1)));
			if(i) res.pb(mp(sx+i,sy+(sy>ty?-1:1)));
		}
	}else if(sy == ty){
		for(int i=0; i<rem/2; i++){
			res.pb(mp(sx+(sx>tx?-1:1),sy-i));
			if(i) res.pb(mp(sx+(sx>tx?-1:1),sy+i));
		}
	}else if(sy < ty){
		if(sx < tx){
			for(int i=0; i<rem/2; i++){
				res.pb(mp(sx-i,sy+1));
				res.pb(mp(sx+1,sy-i));
			}
		}else{
			for(int i=0; i<rem/2; i++){
				res.pb(mp(sx-1,sy-i));
				res.pb(mp(sx+i,sy+1));
			}
		}
	}else{
		if(sx < tx){
			for(int i=0; i<rem/2; i++){
				res.pb(mp(sx-i,sy-1));
				res.pb(mp(sx+1,sy+i));
			}
		}else{
			for(int i=0; i<rem/2; i++){
				res.pb(mp(sx-1,sy+i));
				res.pb(mp(sx+i,sy-1));
			}
		}
	}
	printf("%d\n",(int)res.size());
	for(pii check:res)
		printf("%d %d\n",check.first,check.second);
}
/*
2 0
0 1
5
 */

Compilation message (stderr)

towerdefense.cpp: In function 'int main()':
towerdefense.cpp:49:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d %d %d %d",&sx,&sy,&tx,&ty,&d);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 25 / 25
• Subtask 2: 28 / 28
• Subtask 3: 47 / 47