201409-2 画图

#include <iostream>
using namespace std;
const int N = 110;
int st[N][N];
int main()
{
    int n;
    cin >> n;
    int x1, y1, x2, y2;
    for (int i = 0; i < n; i ++ )
    {
        cin >> x1 >> y1 >> x2 >> y2;
        for (int i = x1; i < x2; i ++ )
            for (int j = y1; j < y2; j ++ ) 
                st[i][j] = 1;
    }
    int res = 0;
    for (int i = 0; i < N; i ++ ) 
        for (int j = 0; j < N; j ++ ) 
            res += st[i][j];
    cout << res << endl;
    return 0;
}