A61547 | 阅读程序：#include <cstdio>

阅读程序：

#include <cstdio>
const int N = 5010;
const int M = 20010;
const int inf = 1073741823;
int e, bg[N], nx[M], to[M], wt[M];
inline void link(int u, int v, int w) {
    to[++e] = v;
    nx[e] = bg[u];
    wt[e] = w;
    bg[u] = e;
}
int n, m, u, v, w;
int f[N], h[N << 1];
void update(int x, int y) {
    x += n - 1;
    for (h[x] = y; x; x >>= 1)
        h[x >> 1] = f[h[x]] < f[h[x^1]] ? h[x] : h[x^1];
}
int main() {
    scanf("%d%d", &n, &m);
    for (int i = 0; i != m; ++i) {
        scanf("%d%d%d", &u, &v, &w);
        link(u, v, w);
    }
int nn = n << 1;
for (int i = 1; i <= n; ++i) {
    for (int j = 1; j != nn; ++j)
        h[j] = 0;
    for (int j = 0; j <= n; ++j)
        f[j] = inf;
    f[i] = 0;
    update(i, i);
    for (int j = i; true; j = h[1]) {
        if (f[j] == inf) break;
        for (int k = bg[j]; k; k = nx[k]) {
            if (f[j] + wt[k] < f[to[k]]) {
                f[to[k]] = f[j] + wt[k];
                update(to[k], to[k]);
            }
        }
        update(j, 0);
     }
    for (int j = 1; j <= n; ++j)
        printf("%d%c", f[j], "\n "[j != n]);
    }
    return 0;
}

以下程序的输入是一张带边权的有向图，完成下面的判断题和单选题: