oj.uz

Submission #88889

# Submission time Handle Problem Language Result Execution time Memory
88889 2018-12-09T18:21:26 Z sailormoon Triumphal arch (POI13_luk) C++14
0 / 100
 364 ms 34336 KB 
#include <string>
#include <algorithm>
#include <iostream>
#include <vector>

using namespace std;
int canHandle(int v, int crs);
vector<vector<int>> graph (1000001); // size
bool visited[1000001];


int main() { 
    int n, a, b, start = 0, midpoint, end, cities; // n -> towns, a -> from, b -> to
    scanf("%d", &n);

    if (n == 0 || n == 1) {
        printf("%d\n", start);
        return 0;
    } 
    cities = n; // for further usage
    end = n; // last point
    n--;
    while (n--) {
        scanf("%d %d", &a, &b);
        graph[a].push_back(b);
        graph[b].push_back(a);
    }

    // binary search for sufficient amount of crews
    while (start < end) {
        midpoint = (start + end) / 2;
        for (int i = 1; i <= cities; i++) visited[i] = false; // clear array 
        if (canHandle(midpoint, 1) == 0) 
            end = midpoint;
        else   
            start = ++midpoint; 
    }
    // if (start == 1) start = 0;
    printf("%d\n", start);

    return 0;
}

int canHandle(int crs, int v) {
    int num_children = 0, need_crews = 0;

    visited[v] = true;

    for (int i = 0; i < graph[v].size(); i++) {
        if (!visited[graph[v][i]]) { 
            num_children++;
            need_crews += canHandle(graph[v][i], crs);
        }
    }
    // if (num_children + need_crews - crs <= 0)
    //     return 0;
    // return num_children + need_crews - crs;
    return max(0, num_children + need_crews - crs);
}

Compilation message

luk.cpp: In function 'int canHandle(int, int)':
luk.cpp:49:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < graph[v].size(); i++) {
                     ~~^~~~~~~~~~~~~~~~~
luk.cpp: In function 'int main()':
luk.cpp:14:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
luk.cpp:24:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &a, &b);
         ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 24 ms 23800 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 24 ms 24052 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 25 ms 24052 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 25 ms 24052 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 30 ms 24316 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #6
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 43 ms 24968 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #7
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 95 ms 27408 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #8
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 206 ms 30880 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #9
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 364 ms 34180 KB Output isn't correct

Subtask #10
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 315 ms 34336 KB Output isn't correct
2 Halted 0 ms 0 KB -