Submission #1774638

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;

struct Edge
{
    int to, nxt;
};
Edge e[100010];
int head[100010], cnt;
const int LG = 60;
int dp[100010][LG + 1];

void add_edge(int a, int b)
{
    e[++cnt].to = b;
    e[cnt].nxt = head[a];
    head[a] = cnt;
}

void dfs(int nod, int tata)
{
    for (int i = head[nod]; i; i = e[i].nxt) {
        int v = e[i].to;
        if (v == tata)
            continue;
        dfs(v, nod);
        for (int j(1); j <= LG; j++)
            dp[nod][j] += dp[v][j];
    }
    int bigg0(1);
    for (int i(1); i <= LG; i++) {
        if (dp[nod][i] <= 1)
            continue;
        int p(i);
        while (dp[nod][p])
            p++;
        dp[nod][p] = 1;
        for (int i(bigg0); i < p; i++)
            dp[nod][i] = 0;
        bigg0 = p;
    }

    int p(1);
    while (dp[nod][p])
        p++;
    dp[nod][p] = 1;
    for (int i(1); i < p; i++)
        dp[nod][i] = 0;
}

int main()
{
    int n, a, b;
    scanf("%d", &n);

    while (--n) {
        scanf("%d%d", &a, &b);
        add_edge(a, b);
        add_edge(b, a);
    }

    dfs(1, 0);

    for (int i(LG); ; i--) {
        if (dp[1][i]) {
            printf("%d\n", i - 1);
            return 0;
        }
    }
    assert(false);
    return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:54:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
                    ^
./Main.cpp:57:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &a, &b);
                              ^

Judge Result