Submission #161836

#	Time	Username	Problem	Language	Result	Execution time	Memory
161836		Akashi	Chase (CEOI17_chase)	C++14	100 / 100	913 ms	346012 KiB

chase

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

int n, V;
int val[100005];
bool viz[100005];
long long Sol, sum[100005];
long long down[100005][105][2], up[100005][105][2];
long long up2[100005][105][2], down2[100005][105][2];
long long up3[100005][105][2];

vector <int> v[100005];

void dfs(int nod = 1){
    viz[nod] = 1;

    down[nod][1][1] = max(down[nod][1][1], sum[nod]);
    up[nod][1][1] = max(up[nod][1][1], sum[nod]);

    for(auto fiu : v[nod]){
        if(viz[fiu]) continue ;

        dfs(fiu);

        for(int k = 0; k <= V ; ++k){
            Sol = max(Sol, down[nod][k][0] + up[fiu][V - k][0]);
            Sol = max(Sol, down[nod][k][0] + up[fiu][V - k][1]);
            Sol = max(Sol, down[nod][k][1] + up[fiu][V - k][0] - val[fiu]);
            Sol = max(Sol, down[nod][k][1] + up[fiu][V - k][1] - val[fiu]);

            Sol = max(Sol, down[fiu][k][0] + up[nod][V - k][0]);
            Sol = max(Sol, down[fiu][k][0] + up[nod][V - k][1]);
            Sol = max(Sol, down[fiu][k][1] + up[nod][V - k][0] - val[nod]);
            Sol = max(Sol, down[fiu][k][1] + up[nod][V - k][1] - val[nod]);
        }

        for(int k = 1; k <= V ; ++k){
            down[nod][k][0] = max(max(down[nod][k - 1][0], down[nod][k][0]), max(down[fiu][k][0], down[fiu][k][1] - val[nod]));
            down[nod][k][1] = max(max(down[nod][k - 1][1], down[nod][k][1]), max(down[fiu][k - 1][0], down[fiu][k - 1][1] - val[nod]) + sum[nod]);

            up[nod][k][0] = max(max(up[nod][k][0], up[nod][k - 1][0]), max(up[fiu][k][0], up[fiu][k][1]));
            up[nod][k][1] = max(max(up[nod][k][1], up[nod][k - 1][1]), max(up[fiu][k - 1][0] - val[fiu], up[fiu][k - 1][1] - val[fiu]) + sum[nod]);

            Sol = max(Sol, max(up[nod][k][0], up[nod][k][1]));
            Sol = max(Sol, max(down[nod][k][0], down[nod][k][1]));
        }
    }
}

int main()
{
//    freopen("1.in", "r", stdin);

    scanf("%d%d", &n, &V);
    for(int i = 1; i <= n ; ++i)
        scanf("%d", &val[i]);

    int x, y;
    for(int i = 2; i <= n ; ++i){
        scanf("%d%d", &x, &y);

        v[x].push_back(y);
        v[y].push_back(x);

        sum[x] += val[y];
        sum[y] += val[x];
    }

    dfs();

    printf("%lld", Sol);

    return 0;
}

Compilation message (stderr)

chase.cpp: In function 'int main()':
chase.cpp:54:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d", &n, &V);
     ~~~~~^~~~~~~~~~~~~~~~
chase.cpp:56:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &val[i]);
         ~~~~~^~~~~~~~~~~~~~~
chase.cpp:60:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &x, &y);
         ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 30 / 30
• Subtask 4: 30 / 30