oj.uz

Submission #908467

# Submission time Handle Problem Language Result Execution time Memory
908467 2024-01-16T12:34:05 Z nightfal Simurgh (IOI17_simurgh) C++14
0 / 100
 42 ms 432 KB 
#include <cstdio>
#include <iostream>
#include <cassert>
#include <vector>
#include <cstdlib>
#include <string>

using namespace std;

static int MAXQ = 30000;

static int n, m, q = 0;
static vector<int> u, v;
static vector<bool> goal;

std::vector<int> find_roads(int n, std::vector<int> u, std::vector<int> v);
int count_common_roads(const std::vector<int>& r);

bool isSubtask1(int n) {return n<=7;}
bool isSubtask2(int n) {return n<=50;}
bool isSubtask3(int n) {return n<=240;}

bool hasBackEdge(int parent, int now, std::vector<int>& visit, std::vector<vector<int>>& edgeL) {
    visit[now]=1;
    // printf("hasBackEdge: parent=%d, now=%d\n",parent,now);
    // for(int i=0; i<visit.size() ;i++) printf("%d ",visit[i]); cout << endl;

    for(int elem: edgeL[now]) {
        if (elem==parent) continue;
        if (visit[elem] || hasBackEdge(now,elem,visit,edgeL)) {/*printf("Edge: %d -> %d\n",now,elem);*/ return true;}
    }
    return false;
}

bool isTree(std::vector<int>& r, std::vector<int>& u, std::vector<int>& v) {
    n = r.size()+1;
    std::vector<vector<int>> edgeL(n);
    for(int i=0; i<n-1; i++) {
        int s = u[r[i]], e=v[r[i]];
        edgeL[s].push_back(e);
        edgeL[e].push_back(s);
    }

    // if (r[0] >=3) {
    //     cout << "edge numbers: "; for(int elem: r) cout << elem << " "; cout << endl;
    //     cout << "edge List\n";
    //     for(int i=0; i<n; i++) {
    //         printf("%d: ", i);
    //         for(int elem: edgeL[i]) printf("%d ",elem); cout << endl;
    //     }
    // }
    
    vector<int> visit(n,0);
    if (hasBackEdge(-1,u[r[0]],visit,edgeL)) return false;
    else {/* cout<< "isTree\n";*/ return true;}
}
bool selectEdges(int cnt, int start, int n, int m, std::vector<int>& r, std::vector<int>& u, std::vector<int>& v){
    if (cnt == n-1){
        if(isTree(r,u,v) && count_common_roads(r)==n-1) return true;
        else return false;
    }
    for(int i=start; i<m; i++){
        r[cnt] = i;
        if (selectEdges(cnt+1,i+1,n,m,r,u,v)) return true;
    }
    return false;
}
std::vector<int> subtask1(int n, std::vector<int>& u, std::vector<int>& v) {
    int m = u.size();
    std::vector<int> r(n-1), zero(n-1,-1);
    if (selectEdges(0,0,n,m,r,u,v)) return r;
    else return zero;
}

std::vector<int> find_roads(int n, std::vector<int> u, std::vector<int> v) {
    // if (isSubtask1(n)) 
    return subtask1(n,u,v);
}

Compilation message

simurgh.cpp:12:18: warning: 'q' defined but not used [-Wunused-variable]
   12 | static int n, m, q = 0;
      |                  ^
simurgh.cpp:12:15: warning: 'm' defined but not used [-Wunused-variable]
   12 | static int n, m, q = 0;
      |               ^
simurgh.cpp:10:12: warning: 'MAXQ' defined but not used [-Wunused-variable]
   10 | static int MAXQ = 30000;
      |            ^~~~

Subtask #1
0 / 13.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 348 KB WA in grader: NO
2 Halted 0 ms 0 KB -

Subtask #2
0 / 17.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 348 KB WA in grader: NO
2 Halted 0 ms 0 KB -

Subtask #3
0 / 21.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 348 KB WA in grader: NO
2 Halted 0 ms 0 KB -

Subtask #4
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 432 KB correct
2 Incorrect 42 ms 348 KB WA in grader: NO
3 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 348 KB WA in grader: NO
2 Halted 0 ms 0 KB -