Submission #1200438

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Source Code Expand

#include <cstdio>
#include <cstring>
#include <vector>
#include <algorithm>

typedef long long i64;

const int N = 200000 + 10;

struct Edge {
  int x, y, z;
  Edge() {}
  Edge(int _x, int _y, int _z): x(_x), y(_y), z(_z) {}
  inline bool operator< (const Edge &rhs) const {
    return z < rhs.z;
  }
};

inline void check(int &lhs, int rhs) { lhs = (lhs < rhs ? lhs : rhs); }

int n, tag[N];
std::vector<Edge> edge;

void init() {
  int m;
  scanf("%d%d", &n, &m);
  memset(tag, 0x3f, sizeof tag);
  while (m--) {
    int a, b, c;
    scanf("%d%d%d", &a, &b, &c);
    edge.push_back(Edge(a, b, c));
    check(tag[a], c + 1);
    check(tag[b], c + 2);
  }
  for (int i = 0; i < 3 * n; ++i) check(tag[(i + 1) % n], tag[i] + 2);
}

int anc[N];
int find(int x) { return anc[x] == x ? x : (anc[x] = find(anc[x])); }

int main() {
  init();
  for (int i = 0; i < n; ++i) edge.push_back(Edge(i, (i + 1) % n, tag[i]));
  std::sort(edge.begin(), edge.end());
  for (int i = 0; i < n; ++i) anc[i] = i;
  i64 ans = 0;
  for (int i = 0; i < edge.size(); ++i) {
    int x = find(edge[i].x), y = find(edge[i].y), z = edge[i].z;
    if (x != y) anc[x] = y, ans += z;
  }
  printf("%lld\n", ans);
  return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘void init()’:
./Main.cpp:26:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &n, &m);
                        ^
./Main.cpp:30:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d", &a, &b, &c);
                                ^

Judge Result