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#96646#5036. 卑鄙的下毒人WatwareCompile Error//C++142.2kb2023-04-14 23:18:522023-04-14 23:18:57

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你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2023-04-14 23:18:57]
  • 评测
  • [2023-04-14 23:18:52]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
const int N = 301000, M = 100100;
int head[N], cur[N], to[M], nxt[M], n, m, s, t, tot = 2, u, v, q[N * 10000];
i64 val[M], w[M], a, b, dis[M];
bool in[N], vis[N];
inline void add(int u, int v, i64 a, i64 b) {
    // printf("add %d -> %d : cap = %d, cost = %d\n", u, v, a, b);
    to[tot] = v, nxt[tot] = head[u], val[tot] = a, w[tot] = b, head[u] = tot++;
    to[tot] = u, nxt[tot] = head[v], val[tot] = 0, w[tot] = -b, head[v] = tot++;
}
inline bool spfa() {
    memset(dis, 0x3f, sizeof(dis)), memcpy(cur, head, sizeof(head));
    int l = 0, r = -1;
    dis[s] = 0, in[s] = 1, q[++r] = s;
    while (l <= r)
        for (int o = q[l++], i = ((in[o] = 0), head[o]); i; i = nxt[i])
            if (val[i] && dis[to[i]] > dis[o] + w[i]) {
                dis[to[i]] = dis[o] + w[i];
                if (!in[to[i]]) in[to[i]] = 1, q[++r] = to[i];
            }
    // printf("spfa result :\n");
    // for (int i = 1; i <= n + 2; i++) printf("%d : %lld\n", i, dis[i]);
    return dis[t] != dis[0];
}
i64 cost, flow;
i64 dfs(int n, i64 fl) {
    i64 lf = fl;
    vis[n] = 1;
    if (n == t) return vis[n] = 0, fl;
    for (int &i = cur[n]; i; i = nxt[i])
        if (!vis[to[i]] && dis[to[i]] == dis[n] + w[i] && val[i]) {
            i64 t = dfs(to[i], min(val[i], lf));
            val[i] -= t, val[i ^ 1] += t, cost += t * w[i], lf -= t;
            if (!lf) return vis[n] = 0, fl;
        }
    vis[n] = 0;
    return fl - lf;
}
void dinic() {
    while (spfa()) flow += dfs(s, LONG_LONG_MAX); //printf("%d\n", flow);
}
int k;
int main() {
    // scanf("%d%d%d%d", &n, &m, &s, &t);
    // for (int i = 1; i <= m; i++) scanf("%d%d%lld%lld", &u, &v, &a, &b), add(u, v, a, b);
    // dinic();
    // printf("%lld %lld\n", flow, cost);
    scanf("%d%d%d", &n, &m, &k);
    s = n + 1, t = n + 2;
    add(s, 1, 100, 0), add(n, t, k, 0); 
    for (int i = 2; i <= n; i++) add(i - 1, i, 100, 0);
    for (int i = 1; i <= m; i++) {
        int l, r, a;
        scanf("%d%d%d", &l, &r, &a);
        l--, l = l ? l : s;
        // printf("!!! %d %d\n", l, r);
        add(l, r, 1, -a);
    }
    dinic();
    printf("%lld\n", -cost);
    // printf("%lld\n", flow);
    return 0;
}

详细

answer.code:5:68: warning: integer overflow in expression of type ‘int’ results in ‘-1284967296’ [-Woverflow]
    5 | int head[N], cur[N], to[M], nxt[M], n, m, s, t, tot = 2, u, v, q[N * 10000];
      |                                                                  ~~^~~~~~~
answer.code:5:68: error: size ‘-1284967296’ of array ‘q’ is negative
answer.code: In function ‘int main()’:
answer.code:50:10: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   50 |     scanf("%d%d%d", &n, &m, &k);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~
answer.code:56:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   56 |         scanf("%d%d%d", &l, &r, &a);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~