深搜灌水 + 皮克定理
1 #include <bits/stdc++.h> 2 #define For(i,j,k) for(int i=j;i<=k;i++) 3 #define LL long long 4 using namespace std ; 5 6 struct point{ 7 int x,y ; 8 }p[111] ; 9 int n,tmp[211][411],mp[211][411],a,b,s ; 10 11 inline LL read() 12 { 13 LL x = 0 , f = 1 ; 14 char ch = getchar() ; 15 while(ch<'0'||ch>'9') { if(ch=='-') f = -1 ; ch = getchar() ; } 16 while(ch>='0'&&ch<='9') { x = x * 10+ch-48 ; ch = getchar() ; } 17 return x * f ; 18 } 19 20 inline void dfs(int x,int y) 21 { 22 if(mp[x][y]) return ; 23 mp[x][y] = 1 ,b++ ; 24 dfs(x+1,y) ; dfs(x,y+1) ; 25 dfs(x-1,y) ; dfs(x,y-1) ; 26 } 27 28 int main() 29 { 30 n = read() ; 31 For(i,1,n) { 32 p[ i ].x = read() ; 33 p[ i ].y = read() ; 34 } 35 p[n+1] = p[1] ; 36 For(i,1,n) { 37 if(p[i].x==p[i+1].x) { 38 a+=abs(p[i+1].y-p[i].y) ; 39 For(j,min(p[i].y,p[i+1].y),max(p[i].y,p[i+1].y)) 40 mp[p[i].x][j] = 1 ; 41 } 42 else{ 43 a+=abs(p[i+1].x-p[i].x) ; 44 For(j,min(p[i].x,p[i+1].x),max(p[i].x,p[i+1].x)) 45 mp[j][p[i].y] = 1 ; 46 } 47 } 48 dfs( p[1].x+1,p[1].y+1 ) ; 49 printf("%d ",a/2+b-1) ; 50 return 0 ; 51 }