版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/TheWildPointer/article/details/84489859
#include <iostream>
using namespace std;
const int N = 2005;
struct Time{
int x, y;
}h[N],w[N];
int main()
{
int n;
cin >> n;
for (int i = 1; i <= n; i++) {
cin >> h[i].x>>h[i].y;
}
for (int i = 1; i <= n; i++) {
cin >> w[i].x >> w[i].y;
}
long long aus = 0;
for (int i = 1, j = 1; i <= n && j <= n;) {
if (h[i].x<w[j].x){
if (h[i].y<=w[j].x){
i++;
}
else if (h[i].y <= w[j].y)
{
aus +=h[i].y - w[j].x;
i++;
}
else {
aus += w[j].y - w[j].x;
j++;//
}
}
else
{
if (h[i].x >= w[j].y) {
j++;
}
else if (h[i].y >= w[j].y)
{
aus += w[j].y - h[i].x;
j++;
}
else {
aus += h[i].y - h[i].x;
i++;
}
}
}
cout << aus;
return 0;
}