func_code_string: #include <bits/stdc++.h>   using namespace std;   inline long long read() {     long long x = 0, f = 1;     char ch = getchar();     while (ch <  0  || ch >  9 ) {       if (ch ==  - ) f = -1;       ch = getchar();     }     while (ch >=  0  && ch <=  9 ) {       x = x * 10 + ch -  0 ;       ch = getchar();     }     return x * f;   }   double p[200010];   int n, cnt;   double ans;   inline void solve(int a, int b) {     ans += (double)(a - b) / 2;     p[++cnt] = (double)(a + b) / 2;   }   int main() {     n = read();     for (int i = 1; i <= n; i++) {       long long a = read(), b = read(), c = read(), d = read();       if (a + b >= c + d) {         solve(a, b);         solve(c, d);       } else {         if (a >= d) solve(a - d, d - a);         if (b >= c) solve(c - b, b - c);       }     }     sort(p + 1, p + cnt + 1, greater<double>());     for (int i = 1; i <= cnt; i++) {       if (i & 1)         ans += p[i];       else         ans -= p[i];     }     printf( %.0f n , ans);   }   