Submission #261821

#	Time	Username	Problem	Language	Result	Execution time	Memory
261821		cheeheng	Colors (RMI18_colors)	C++14	22 / 100	92 ms	7552 KiB

colors

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

typedef pair<int, int> ii;

vector<int> AdjList[150005];
int a[150005];
int b[150005];
ii ab[150005];
int deg[150005];
bool visited[150005];

int c[150005];
int d[150005];
int pos[150005];

vector<int> toposort;

void dfs1(int u){
    if(visited[u]){return;}
    visited[u] = true;
    for(int v: AdjList[u]){
        if(!visited[v]){
            dfs1(v);
        }
    }
    toposort.push_back(u);
}

int main(){
    int t;
    scanf("%d", &t);

    while(t --){
        int N, M;
        scanf("%d%d", &N, &M);

        for(int i = 1; i <= N; i ++){
            AdjList[i].clear();
            deg[i] = 0;
        }

        set<int> s1;
        for(int i = 1; i <= N; i ++){
            scanf("%d", &a[i]);
            s1.insert(a[i]);
        }

        for(int i = 1; i <= N; i ++){
            scanf("%d", &b[i]);
        }

        for(int i = 0; i < M; i ++){
            int u, v;
            scanf("%d%d", &u, &v);
            AdjList[u].push_back(v);
            AdjList[v].push_back(u);
            deg[u] ++;
            deg[v] ++;
        }

        int ans = 1;
        for(int i = 1; i <= N; i ++){
            if(b[i] > a[i] || s1.find(b[i]) == s1.end()){
                ans = 0;
                break;
            }
        }

        if(ans == 0){
            printf("0\n");
            continue;
        }

        int starVertex = -1;
        for(int i = 1; i <= N; i ++){
            if(deg[i] == N-1){
                starVertex = i;
                break;
            }
        }

        int cntDeg1 = 0;
        for(int i = 1; i <= N; i ++){
            cntDeg1 += (deg[i] == 1);
        }


        if((long long)M == (long long)N*(N-1)/2){
            multiset<int> s;
            for(int i = 1; i <= N; i ++){
                ab[i] = ii(a[i], b[i]);
                s.insert(a[i]);
            }
            sort(ab+1, ab+(N+1), greater<ii>());

            for(int i = 1; i <= N; i ++){
                if(ab[i].first == ab[i].second){continue;}
                if(ab[i].first < ab[i].second){
                    ans = 0;
                    break;
                }
                if(s.find(ab[i].second) != s.end()){

                }else{
                    ans = 0;
                    break;
                }

                s.erase(s.find(ab[i].first));
            }
            printf("%d\n", ans);
            continue;
        }

        if(starVertex != -1 && M == N-1){
            for(int i = 1; i <= N; i ++){
                if(i == starVertex){continue;}
                if(b[i] <= a[starVertex] && b[i] >= b[starVertex] || b[i] == a[i]){
                }else{
                    ans = 0;
                    break;
                }
            }
            printf("%d\n", ans);
            continue;
        }

        if(cntDeg1 == 2 && M == N-1){
            int root = -1;
            for(int i = 1; i <= N; i ++){
                if(deg[i] == 1){
                    root = i;
                    break;
                }
            }

            for(int i = 1; i <= N; i ++){
                visited[i] = 0;
            }

            toposort = vector<int>();
            dfs1(root);

            /*
            for(int i = 1; i <= N; i ++){
                printf("%d ", toposort[i-1]);
            }
            printf("\n");
            */

            for(int i = 1; i <= N; i ++){
                pos[toposort[i-1]] = i;
            }

            for(int i = 1; i <= N; i ++){
                c[pos[i]] = a[i];
                d[pos[i]] = b[i];
            }

            /*
            printf("DEBUG:\n");
            for(int i = 1; i <= N; i ++){
                printf("%d ", c[i]);
            }
            printf("\n");

            for(int i = 1; i <= N; i ++){
                printf("%d ", d[i]);
            }
            printf("\n");
            */


            c[N+1] = -1;
            d[N+1] = -1;
            int curVal = d[1];
            int rangeMin = c[1];
            ans = 1;
            for(int i = 2; i <= N+1; i ++){
                if(d[i] != d[i-1]){
                    if(rangeMin != curVal){
                        ans = 0;
                        break;
                    }
                    rangeMin = c[i];
                    curVal = d[i];
                }else{
                    rangeMin = min(c[i], rangeMin);
                }
            }
            printf("%d\n", ans);
            continue;
        }

        throw;
    }

    return 0;
}

Compilation message (stderr)

colors.cpp: In function 'int main()':
colors.cpp:119:42: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
                 if(b[i] <= a[starVertex] && b[i] >= b[starVertex] || b[i] == a[i]){
                    ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
colors.cpp:32:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &t);
     ~~~~~^~~~~~~~~~
colors.cpp:36:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &N, &M);
         ~~~~~^~~~~~~~~~~~~~~~
colors.cpp:45:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d", &a[i]);
             ~~~~~^~~~~~~~~~~~~
colors.cpp:50:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d", &b[i]);
             ~~~~~^~~~~~~~~~~~~
colors.cpp:55:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d%d", &u, &v);
             ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 7 / 7
• Subtask 3: 0 / 8
• Subtask 4: 0 / 15
• Subtask 5: 0 / 7
• Subtask 6: 0 / 16
• Subtask 7: 0 / 10
• Subtask 8: 0 / 22