oj.uz

Submission #187258

# Submission time Handle Problem Language Result Execution time Memory
187258 2020-01-12T14:59:31 Z Ruxandra985 Alternating Current (BOI18_alternating) C++14
19 / 100
 52 ms 5624 KB 
#include <bits/stdc++.h>
#define DIMN 100010
using namespace std;
pair <int,pair <int,int> > v[DIMN],w[DIMN];
int sol[DIMN] , par[DIMN] , sp1[DIMN] , sp2[DIMN];
set <pair <int,int> > s;
int common (int last , int c){

    if (!last)
        return 0;

    if (v[last].first <= v[last].second.first){

        if (v[c].first <= v[c].second.first){

            if (v[c].first <= v[last].second.first)
                return 1;
            return 0;

        }
        else {

            if (v[c].first <= v[last].second.first)
                return 1;
            return 0;

        }

    }
    else {

        if (v[c].first <= v[c].second.first){

            if (v[c].first <= v[last].second.first)
                return 1;
            return 0;

        }
        else {

            if (v[c].second.first > v[last].second.first)
                return 1;
            return 0;

        }

    }

}
int main()
{
    FILE *fin = stdin;
    FILE *fout = stdout;
    int n , m , i , maxi , poz, poz2 , maxi2, last;
    fscanf (fin,"%d%d",&n,&m);
    maxi = 0;
    poz = 0;
    for (i=1;i<=m;i++){
        fscanf (fin,"%d%d",&v[i].first,&v[i].second.first);
        v[i].second.second = i;
        w[i] = v[i];
    }
    maxi2 = 0;
    poz2 = 0;
    sort (v + 1 , v + m + 1);
    for (i=1;i<=m;i++){
        if (v[i].first > v[i].second.first && maxi < v[i].second.first){
            maxi = v[i].second.first;
            poz = i;
        }
    }
    for (i=1;i<=m;i++){
        /// check daca i e inclus total in vreun alt interval
        if (v[i].first <= v[i].second.first){ /// e un interval normal
            if (maxi > v[i].second.first){ /// e inclus
                par[i] = poz;
                continue;
            }
            else{
                maxi = v[i].second.first;
                poz = i;
            }
        }
        else {
            maxi = n; /// le tratezi ca pe doua intervale
            poz = i;
            if (maxi2 > v[i].second.first){ /// e inclus
                par[i] = poz2;
                continue;
            }
            else {
                maxi2 = v[i].second.first;
                poz2 = i;
            }
        }
        par[i] = -1; /// e tata
    }
    /// daca au ceva in comun, pui semne opuse
    last = 0;
    for (i=1;i<=m;i++){
        if (par[i] == -1){

            if (common(last , i)){
                sol[v[i].second.second] = 1 - sol[v[last].second.second];
            }
            else {
                sol[v[i].second.second] = 0;
            }

            last = i;
        }
        else {
            sol[v[i].second.second] = 1 - sol[v[par[i]].second.second];
        }
    }

    for (i=1;i<=m;i++){
        if (w[i].first <= w[i].second.first){
            if (sol[i] == 1){
                sp1[w[i].first]++;
                sp1[w[i].second.first+1]--;
            }
            else {
                sp2[w[i].first]++;
                sp2[w[i].second.first+1]--;
            }
        }
        else {
            if (sol[i] == 1){
                sp1[w[i].first]++;
                sp1[1]++;
                sp1[w[i].second.first+1]--;
            }
            else {
                sp2[w[i].first]++;
                sp2[1]++;
                sp2[w[i].second.first+1]--;
            }
        }
    }

    for (i=1;i<=n;i++){
        sp1[i] += sp1[i-1];
        sp2[i] += sp2[i-1];

        if (!sp1[i] || !sp2[i]){
            fprintf (fout,"impossible\n");
            return 0;
        }

    }

    for (i=1;i<=m;i++){
        fprintf (fout,"%d",sol[i]);
    }
    return 0;
}

Compilation message

alternating.cpp: In function 'int main()':
alternating.cpp:55:12: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     fscanf (fin,"%d%d",&n,&m);
     ~~~~~~~^~~~~~~~~~~~~~~~~~
alternating.cpp:59:16: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         fscanf (fin,"%d%d",&v[i].first,&v[i].second.first);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 376 KB Output is correct
2 Correct 0 ms 248 KB Output is correct
3 Correct 2 ms 364 KB Output is correct
4 Incorrect 2 ms 380 KB 'impossible' claimed, but there is a solution
5 Halted 0 ms 0 KB -

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 376 KB Output is correct
2 Correct 0 ms 248 KB Output is correct
3 Correct 2 ms 364 KB Output is correct
4 Incorrect 2 ms 380 KB 'impossible' claimed, but there is a solution
5 Halted 0 ms 0 KB -

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 376 KB Output is correct
2 Correct 0 ms 248 KB Output is correct
3 Correct 2 ms 364 KB Output is correct
4 Incorrect 2 ms 380 KB 'impossible' claimed, but there is a solution
5 Halted 0 ms 0 KB -

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 5240 KB Output is correct
2 Correct 4 ms 1144 KB Output is correct
3 Correct 15 ms 2936 KB Output is correct
4 Correct 18 ms 3320 KB Output is correct
5 Correct 47 ms 5268 KB Output is correct
6 Correct 42 ms 5368 KB Output is correct
7 Correct 43 ms 5084 KB Output is correct
8 Correct 4 ms 1400 KB Output is correct
9 Correct 3 ms 1144 KB Output is correct
10 Correct 49 ms 5496 KB Output is correct
11 Correct 39 ms 4344 KB Output is correct
12 Correct 42 ms 5104 KB Output is correct
13 Correct 12 ms 1144 KB Output is correct
14 Correct 3 ms 1148 KB Output is correct
15 Correct 52 ms 5508 KB Output is correct
16 Correct 17 ms 3296 KB Output is correct
17 Correct 49 ms 5624 KB Output is correct
18 Correct 47 ms 4600 KB Output is correct
19 Correct 5 ms 1400 KB Output is correct
20 Correct 45 ms 5112 KB Output is correct

Subtask #5
0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 376 KB Output is correct
2 Correct 0 ms 248 KB Output is correct
3 Correct 2 ms 364 KB Output is correct
4 Incorrect 2 ms 380 KB 'impossible' claimed, but there is a solution
5 Halted 0 ms 0 KB -