oj.uz

Submission #88891

# Submission time Handle Problem Language Result Execution time Memory
88891 2018-12-09T18:30:32 Z sailormoon Triumphal arch (POI13_luk) C++14
90 / 100
 1145 ms 38124 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);
        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 = 0; i < cities; i++) visited[i] = false; // clear array 
            if (canHandle(1, midpoint) == 0) 
                end = midpoint;
            else   
                start = midpoint + 1; 
        }
        // if (start == 1) start = 0;
        printf("%d\n", start);
     
        return 0;
    }
     
    int canHandle(int v, int crs) {
        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;
    }

Compilation message

luk.cpp: In function 'int canHandle(int, int)':
luk.cpp:42:27: 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:14:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &n);
         ~~~~~^~~~~~~~~~
luk.cpp:19:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d %d", &a, &b);
             ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 23800 KB Output is correct
2 Correct 25 ms 23804 KB Output is correct
3 Correct 25 ms 23864 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 23996 KB Output is correct
2 Correct 26 ms 23996 KB Output is correct
3 Correct 25 ms 23996 KB Output is correct
4 Incorrect 28 ms 23996 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 23996 KB Output is correct
2 Correct 24 ms 24036 KB Output is correct
3 Correct 23 ms 24036 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 24 ms 24036 KB Output is correct
2 Correct 25 ms 24036 KB Output is correct
3 Correct 25 ms 24176 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 35 ms 24384 KB Output is correct
2 Correct 36 ms 24532 KB Output is correct
3 Correct 30 ms 24532 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 66 ms 25060 KB Output is correct
2 Correct 63 ms 25844 KB Output is correct
3 Correct 44 ms 25844 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 179 ms 27516 KB Output is correct
2 Correct 183 ms 28856 KB Output is correct
3 Correct 117 ms 28856 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 738 ms 30928 KB Output is correct
2 Correct 846 ms 34284 KB Output is correct
3 Correct 245 ms 34284 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1096 ms 34396 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1145 ms 34432 KB Output is correct
2 Correct 1122 ms 38124 KB Output is correct
3 Correct 520 ms 38124 KB Output is correct