ソースコード
#include <bits/stdc++.h>
using namespace std;
#define fs first
#define sc second
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define rep(i, n) for (int i = 0; i < n; ++i)
#define pb emplace_back
using pii = pair<int, int>;
using vi = vector<int>;
using lint = long long;
const int inf = 1001001001;
const lint linf = 1001001001001001001ll;
const int mod = 1e9 + 7;
const int dx[]{0, 1, 0, -1, -1, -1, 1, 1}, dy[]{1, 0, -1, 0, -1, 1, -1, 1};
template<typename T> inline bool chmin(T &a, T b) { if (a > b) { a = b; } return a > b; }
template<typename T> inline bool chmax(T &a, T b) { if (a < b) { a = b; } return a < b; }
template<typename T> inline void print(const T &x, string s = "\n") { cout << x << s; }
template<typename T> inline void print(const vector<T> &v, string s = " ")
{ rep(i, v.size()) cout << v[i] << (i + 1 == v.size() ? "\n" : s); }
inline bool inside(int y, int x, int H, int W) { return 0 <= y && y < H && 0 <= x && x < W; }
inline lint in() { lint x; std::cin>>x; return x; }
struct edge {
edge() {}
edge(int a, int b) { to = a; cost = b; }
int to, cost;
};
int n, k;
int d[5050];
vector<edge> G[5050];
int dijkstra(int s = 0) {
priority_queue<pii, vector<pii>, greater<pii>> q;
fill(d, d + 5050, inf);
d[s] = 0;
q.push(pii(d[s], s));
while (!q.empty()) {
pii p = q.top(); q.pop();
int v = p.sc;
if (d[v] < p.fs) continue;
for (int i = 0; i < G[v].size(); ++i) {
edge e = G[v][i];
if (d[e.to] > d[v] + e.cost) {
d[e.to] = d[v] + e.cost;
q.push(pii(d[e.to], e.to));
}
}
}
return d[n - 1];
}
vi c, r;
vi E[5050];
bool f[5050];
void bfs(int v) {
bool u[5050] = {false};
queue<pii> q;
q.push(pii(v, r[v] + 1));
while (!q.empty()) {
pii p = q.front();
q.pop();
if (p.sc == 0 || u[p.fs]) continue;
u[p.fs] = true;
G[v].pb(edge(p.fs, c[v]));
for (int i = 0; i < E[p.fs].size(); ++i) {
q.push(pii(E[p.fs][i], p.sc - 1));
}
}
}
int main() {
cin >> n >> k;
rep(i, n) { c.pb(in()); r.pb(in()); }
rep(i, k) {
int a = in() - 1, b = in() - 1;
E[a].pb(b);
E[b].pb(a);
}
rep(i, n) bfs(i);
cout << dijkstra() << endl;
}