func_code_string: #include <bits/stdc++.h>   namespace FastIO {   const int SIZE = (1 << 21) + 1;   char ibuf[SIZE], *iS, *iT, obuf[SIZE], *oS = obuf, *oT = oS + SIZE - 1, c,                                          qu[55];   int qr;   inline void flush() {     fwrite(obuf, 1, oS - obuf, stdout);     oS = obuf;   }   inline void putc(char x) {     *oS++ = x;     if (oS == oT) flush();   }   inline void wrap() {     *oS++ =   n ;     if (oS == oT) flush();   }   template <class I>   inline void gi(I &x) {     I sign = 1;     for (c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, SIZE, stdin),                          (iS == iT ? EOF : *iS++))                        : *iS++);          c <  0  || c >  9 ;          c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, SIZE, stdin),                          (iS == iT ? EOF : *iS++))                        : *iS++))       if (c ==  - ) sign = -1;     for (x = 0; c <=  9  && c >=  0 ;          c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, SIZE, stdin),                          (iS == iT ? EOF : *iS++))                        : *iS++))       x = x * 10 + (c & 15);     x *= sign;   }   inline int gi() {     int x, sign = 1;     for (c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, SIZE, stdin),                          (iS == iT ? EOF : *iS++))                        : *iS++);          c <  0  || c >  9 ;          c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, SIZE, stdin),                          (iS == iT ? EOF : *iS++))                        : *iS++))       if (c ==  - ) sign = -1;     for (x = 0; c <=  9  && c >=  0 ;          c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, SIZE, stdin),                          (iS == iT ? EOF : *iS++))                        : *iS++))       x = x * 10 + (c & 15);     return x * sign;   }   inline long long gl() {     long long x, sign = 1;     for (c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, SIZE, stdin),                          (iS == iT ? EOF : *iS++))                        : *iS++);          c <  0  || c >  9 ;          c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, SIZE, stdin),                          (iS == iT ? EOF : *iS++))                        : *iS++))       if (c ==  - ) sign = -1;     for (x = 0; c <=  9  && c >=  0 ;          c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, SIZE, stdin),                          (iS == iT ? EOF : *iS++))                        : *iS++))       x = x * 10 + (c & 15);     return x * sign;   }   template <class I>   inline void print(I &x) {     if (!x) putc( 0 );     while (x) qu[++qr] = x % 10 +  0 , x /= 10;     while (qr) putc(qu[qr--]);   }   template <class I>   inline void println(I &x) {     if (!x) putc( 0 );     while (x) qu[++qr] = x % 10 +  0 , x /= 10;     while (qr) putc(qu[qr--]);     wrap();   }   }  // namespace FastIO   using namespace std;   int n;   struct Rectangle {     int l, r, d, u;   } rec[1000 + 5];   bool solve(vector<Rectangle> v) {     if (v.size() <= 1) return 1;     int maxr = 0, maxu = 0;     bool flag = 0;     vector<Rectangle> pre, suf;     sort(v.begin(), v.end(),          [](const Rectangle &a, const Rectangle &b) { return a.l < b.l; });     for (int i = v.size() - 1; ~i; --i) suf.push_back(v[i]);     for (int i = 0; i < v.size() - 1; ++i) {       pre.push_back(v[i]), suf.pop_back();       maxr = max(maxr, v[i].r);       if (maxr <= v[i + 1].l && solve(pre) && solve(suf)) {         flag = 1;         break;       }     }     if (flag) return true;     sort(v.begin(), v.end(),          [](const Rectangle &a, const Rectangle &b) { return a.d < b.d; });     pre.clear();     suf.clear();     for (int i = v.size() - 1; ~i; --i) suf.push_back(v[i]);     for (int i = 0; i < v.size() - 1; ++i) {       pre.push_back(v[i]), suf.pop_back();       maxu = max(maxu, v[i].u);       if (maxu <= v[i + 1].d && solve(pre) && solve(suf)) {         flag = 1;         break;       }     }     if (flag) return true;     return false;   }   int main() {     scanf( %d , &n);     vector<Rectangle> v;     for (int i = 1, a, b, c, d; i <= n; ++i) {       scanf( %d%d%d%d , &a, &b, &c, &d);       rec[i] = {a, c, b, d};       v.push_back(rec[i]);     }     if (solve(v))       printf( YES n );     else       printf( NO n );     return 0;   }   