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#include <math.h>
#include <iostream>
#include <set>
#include <vector>
using namespace std;
#define ll long long
int tt, tc;

const double PI = acos(-1);
void solve() {
    int n;
    cin >> n;
    vector<pair<int, int>> in(n);
    for (auto& [f, l] : in) cin >> f >> l;
    set<double> angles;
    for (double i = 0; i < 360; i+= 0.5) {
        angles.insert(i);
    }

    auto cross = [&](tuple<double, double, double> a, tuple<double, double, double> b) {
        auto [x1, y1, z1] = a;
        auto [x2, y2, z2] = b;
        return make_tuple(y1 * z2 - z1 * y2, z1 * x2 - x1 * z2, x1 * y2 - y1 * x2);
    };

    auto begin = INT32_MAX, end = INT32_MIN;

    for (int i = 0; i < n; i++) {
        auto [f, l] = in[i];
        auto [f2, l2] = in[(i + 1) % n];
        tuple<double, double, double> p1 = {cos(PI * l / 180.0), sin(PI * l / 180.0), sin(PI * f / 180.0)};
        tuple<double, double, double> p2 = {cos(PI * l2 / 180.0), sin(PI * l2 / 180.0), sin(PI * f2 / 180.0)};
        auto p3 = cross(p1, p2);
        double dot = get<2>(p3);
        if (abs(dot) < 1e-8) return void(cout << "yes\n");
        // walk from l to l2
        auto process = [&](double x){
            auto ret = angles.find(x);
            if(ret != angles.end())
                angles.erase(ret);
        };
        double ld = l + 180, l2d = l2 + 180;
        if (l2d < ld) swap(ld, l2d);
        double dist1 = l2d - ld;
        double dist2 = 360 - dist1;
        double inc = dist2 < dist1 ? -0.5 : 0.5;
        if(ld == l2d){
            process(ld);
        }
        while(ld != l2d) {
            process(ld);
            ld+= inc;
            if(ld < 0) l += 360;
            if(ld >= 360) l -= 360;
        }
    }

    if (angles.empty()) return void(cout << "yes\n");
    cout << "no " << *angles.begin() - 180 << endl;
//    cout << (angles.begin() & 1 ? to_string(angles.begin() / 2) + ".5" : to_string(angles.begin() / 2) + ".0") << '\n';
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    tt = 1, tc = 1;
    // cin >> tt;
    while (tt--) {
        solve();
        tc++;
    }
}