1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 #include #define ll long long using namespace std; struct prost { ll x1, y1, x2, y2; prost(ll _x1, ll _y1, ll _x2, ll _y2) {x1=_x1; y1=_y1; x2=_x2; y2=_y2;} bool operator==(prost a) {return a.x1 == x1 and a.x2 == x2 and a.y1 == y1 and a.y2 == y2;} bool operator<(prost a){return (x2-x1)*(y2-y1) < (a.x2-a.x1)*(a.y2-a.y1);} }; inline ll area(prost a) { if(a.x2 - a.x1 <= 0 or a.y2 - a.y1 <= 0) return 0; return(a.x2 - a.x1) * (a.y2 - a.y1); } prost inter(prost a, prost b) { long long xl, yl, xp, yp; xl = max(a.x1, b.x1); xp = min(a.x2, b.x2); yl = max(a.y1, b.y1); yp = min(a.y2, b.y2); if(xl >= xp or yl >= yp) return prost(0,0,0,0); return prost(xl, yl, xp, yp); } int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); int n; ll x, y; cin >> n >> x >> y; ll xl = 0, yl = 0, xp = x, yp = y; vector v; vector tab; for(int i = 0; i < n; i++) { ll x1, y1, x2, y2; cin >> x1 >> y1 >> x2 >> y2; if(x1 > x2) swap(x1, x2); if(y1 > y2) swap(y1, y2); tab.push_back(prost(x1,y1,x2,y2)); } sort(tab.begin(), tab.end()); for(int i = 0; i < n; i++) { ll x1 = tab[i].x1, x2 = tab[i].x2, y1 = tab[i].y1, y2 = tab[i].y2; //cout << "(" << x1 << "," << y1 << ") (" << x2 << "," << y2 << ")" << endl; if(i == 0) { prost p5 = prost(x1, y1, x2, y2); //in prost p4 = prost(xl, y1, x1, y2); //hor prost p6 = prost(x2, y1, xp, y2); prost p2 = prost(x1, y2, x2, yp); //ver prost p8 = prost(x1, yl, x2, y1); prost p7 = prost(xl, yl, x1, y1); //out prost p1 = prost(xl, y2, x1, yp); prost p3 = prost(x2, y2, xp, yp); prost p9 = prost(x2, yl, xp, y1); ll inside = area(p5); ll hor = area(p4) + area(p6); ll ver = area(p2) + area(p8); ll outside = area(p1) + area(p3) + area(p7) + area(p9); ll m = max(outside, max(hor, max(ver, inside))); vector v1; if(m == inside) { v1.push_back(p5); } else if(m == hor) { v1.push_back(p4); v1.push_back(p6); } else if(m == hor) { v1.push_back(p2); v1.push_back(p8); } else if(m == outside) { v1.push_back(p1); v1.push_back(p3); v1.push_back(p7); v1.push_back(p9); } for(auto x : v1) { if(inter(x, x) == prost(0,0,0,0)) continue; v.push_back(x); } } else { prost p5 = prost(x1, y1, x2, y2); //in prost p4 = prost(xl, y1, x1, y2); //hor prost p6 = prost(x2, y1, xp, y2); prost p2 = prost(x1, y2, x2, yp); //ver prost p8 = prost(x1, yl, x2, y1); prost p7 = prost(xl, yl, x1, y1); //out prost p1 = prost(xl, y2, x1, yp); prost p3 = prost(x2, y2, xp, yp); prost p9 = prost(x2, yl, xp, y1); ll inside = 0; ll hor = 0; ll ver = 0; ll outside = 0; for(auto x : v) { inside += area(inter(p5, x)); hor += area(inter(p4, x)); hor += area(inter(p6, x)); ver += area(inter(p2, x)); ver += area(inter(p8, x)); outside += area(inter(p1, x)); outside += area(inter(p3, x)); outside += area(inter(p7, x)); outside += area(inter(p9, x)); } ll m = max(outside, max(hor, max(ver, inside))); vector v1; if(m == inside) { for(auto x : v) { v1.push_back(inter(p5, x)); } } else if(m == hor) { for(auto x : v) { v1.push_back(inter(p4, x)); v1.push_back(inter(p6, x)); } } else if(m == hor) { for(auto x : v) { v1.push_back(inter(p2, x)); v1.push_back(inter(p8, x)); } } else if(m == outside) { for(auto x : v) { v1.push_back(inter(p1, x)); v1.push_back(inter(p3, x)); v1.push_back(inter(p7, x)); v1.push_back(inter(p9, x)); } } v.erase(v.begin(), v.end()); for(auto x : v1) { if(x == prost(0,0,0,0)) continue; v.push_back(x); } } /*cout << endl; for(auto x : v) { cout << x.x1 << " " << x.y1 << ", " << x.x2 << " " << x.y2 << endl; }*/ } ll s = 0; for(auto x : v) s += area(x); cout << s << endl; }