1210. Kind Spirits - Timus

#include <bits/stdc++.h>
#define INF 0x3f3f3f3f

using namespace std;

inline void min_self(int& a, int b) {
    a = min(a, b);
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int N;
    cin >> N;
    int cost[32][32][32], inLevel[32];
    vector < int > v[32][32];
    for(int i = 1; i <= N; ++i) {
        int K;
        cin >> K;
        inLevel[i] = K;
        for(int j = 1; j <= K; ++j)
            while(true) {
                int a, b;
                cin >> a;
                if(a == 0)
                    break;
                cin >> b;
                v[i][j].push_back(a);
                cost[i][j][a] = b;
            }
        if(i == N)
            break;
        char x;
        cin >> x;
    }
    vector < vector < int > > d(32, vector < int >(32, INF));
    d[0][1] = 0;
    for(int i = 1; i <= N; ++i)
        for(int j = 1; j <= inLevel[i]; ++j)
            for(int k = 0; k < (int)v[i][j].size(); ++k) {
                int x = v[i][j][k];
                if(d[i][j] > d[i - 1][x] + cost[i][j][x])
                    d[i][j] = d[i - 1][x] + cost[i][j][x];
            }
    int ans = INF;
    for(int i = 1; i <= inLevel[N]; ++i)
        min_self(ans, d[N][i]);
    cout << ans;
}