Submission #813655

#	Time	Username	Problem	Language	Result	Execution time	Memory
813655		urd05	Line Town (CCO23_day1problem3)	C++17	13 / 25	149 ms	14220 KiB

Main

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

typedef pair<int,int> P;
priority_queue<P> pq;
int arr[500001];
int n;
int tree[500005];
const long long INF=1e14;

int sum(int i) {
    int ret=0;
    while (i>0) {
        ret+=tree[i];
        i-=(i&-i);
    }
    return ret;
}

void upd(int i,int val) {
    while (i<=n) {
        tree[i]+=val;
        i+=(i&-i);
    }
}

int main(void) {
    scanf("%d",&n);
    for(int i=1;i<=n;i++) {
        scanf("%d",&arr[i]);
        upd(i,1);
        pq.push(P(abs(arr[i]),i));
    }
    int sz=n;
    long long ret=0;
    while (!pq.empty()) {
        int now=pq.top().first;
        if (now==0) {
            break;
        }
        vector<int> vec;
        while (!pq.empty()&&pq.top().first==now) {
            vec.push_back(pq.top().second);
            pq.pop();
        }
        long long value=INF;
        sort(vec.begin(),vec.end());
        vector<int> vec0; //0에서 양수
        vector<int> vec1; //0에서 음수
        for(int i=0;i<vec.size();i++) {
            if ((sum(vec[i])%2==1)^(arr[vec[i]]<0)) {
                vec0.push_back(vec[i]);
            }
            else {
                vec1.push_back(vec[i]);
            }
        }
        bool stone=true;
        bool enone=(sz%2==0);
        long long val=0;
        int k=vec0.size();
//printf("%d %d %d\n",now,vec0.size(),vec1.size());
        if (vec1.size()>vec0.size()+2) {
            printf("-1");
            return 0;
        }
        else if (vec1.size()==vec0.size()+2) {
            if (!enone) {
                printf("-1");
                return 0;
            }
            for(int i=0;i<k;i++) {
                val+=sum(vec1[i]-1);
                upd(vec1[i],-1);
                val+=sum(vec0[i]-1);
                upd(vec0[i],-1);
            }
            val+=sum(vec1[k]-1);
            upd(vec1[k],-1);
            val+=sum(n)-sum(vec1[k+1]);
            upd(vec1[k+1],-1);
            value=min(value,val);
            for(int i=k-1;i>=0;i--) {
                if (vec0[i]<vec1[i+1]) {
                    val++;
                }
                else {
                    val--;
                }
                val-=2*sum(vec0[i])-sum(n);
                val-=2*sum(vec1[i+1])-sum(n);
                value=min(value,val);
            }
        }
        else if (vec1.size()==vec0.size()+1) {
            if (enone) {
                for(int i=0;i<k;i++) {
                    val+=sum(vec1[i]-1);
                    upd(vec1[i],-1);
                    val+=sum(vec0[i]-1);
                    upd(vec0[i],-1);
                }
                val+=sum(vec1[k]-1);
                upd(vec1[k],-1);
                value=min(value,val);
                for(int i=k-1;i>=0;i--) {
                    val-=2*sum(vec1[i+1])-sum(n);
                    value=min(value,val);
                    val-=2*sum(vec0[i])-sum(n);
                    value=min(value,val);
                }
                val-=2*sum(vec1[0])-sum(n);
                value=min(value,val);
            }
            else {
                for(int i=0;i<k;i++) {
                    val+=sum(vec1[i]-1);
                    upd(vec1[i],-1);
                    val+=sum(vec0[i]-1);
                    upd(vec0[i],-1);
                }
                val+=sum(vec1[k]-1);
                upd(vec1[k],-1);
                value=min(value,val);
                for(int i=k-1;i>=0;i--) {
                    if (vec0[i]<vec1[i+1]) {
                        val++;
                    }
                    else {
                        val--;
                    }
                    val-=2*sum(vec0[i])-sum(n);
                    val-=2*sum(vec1[i+1])-sum(n);
                    value=min(value,val);
                }
            }
        }
        else if (vec1.size()==vec0.size()) {
            if (enone) {
                for(int i=0;i<k;i++) {
                    val+=sum(vec1[i]-1);
                    upd(vec1[i],-1);
                    val+=sum(vec0[i]-1);
                    upd(vec0[i],-1);
                }
                value=min(value,val);
                for(int i=k-1;i>=0;i--) {
                    if (vec0[i]>vec1[i]) {
                        val++;
                    }
                    else {
                        val--;
                    }
                    val-=2*sum(vec0[i])-sum(n);
                    val-=2*sum(vec1[i])-sum(n);
                    value=min(value,val);
                }
            }
            else {
                for(int i=0;i<k;i++) {
                    val+=sum(vec1[i]-1);
                    upd(vec1[i],-1);
                    val+=sum(vec0[i]-1);
                    upd(vec0[i],-1);
                }
                value=min(value,val);
                for(int i=k-1;i>=0;i--) {
                    val-=2*sum(vec0[i])-sum(n);
                    value=min(value,val);
                    val-=2*sum(vec1[i])-sum(n);
                    value=min(value,val);
                }
            }
        }
        else if (vec1.size()+1==vec0.size()) {
            if (enone) {
                printf("-1");
                return 0;
            }
            for(int i=0;i<k-1;i++) {
                val+=sum(vec1[i]-1);
                upd(vec1[i],-1);
                val+=sum(vec0[i]-1);
                upd(vec0[i],-1);
            }
            val+=sum(n)-sum(vec0[k-1]);
            upd(vec0[k-1],-1);
            value=min(value,val);
            for(int i=k-2;i>=0;i--) {
                if (vec0[i]>vec1[i]) {
                    val++;
                }
                else {
                    val--;
                }
                val-=2*sum(vec0[i])-sum(n);
                val-=2*sum(vec1[i])-sum(n);
                value=min(value,val);
            }
        }
        else {
            printf("-1");
            return 0;
        }
        ret+=value;
        sz-=vec.size();
    }
    printf("%lld",ret);
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:50:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |         for(int i=0;i<vec.size();i++) {
      |                     ~^~~~~~~~~~~
Main.cpp:58:14: warning: unused variable 'stone' [-Wunused-variable]
   58 |         bool stone=true;
      |              ^~~~~
Main.cpp:28:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
Main.cpp:30:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |         scanf("%d",&arr[i]);
      |         ~~~~~^~~~~~~~~~~~~~

• Subtask 1: 3 / 3
• Subtask 2: 3 / 3
• Subtask 3: 3 / 3
• Subtask 4: 4 / 4
• Subtask 5: 0 / 4
• Subtask 6: 0 / 3
• Subtask 7: 0 / 2
• Subtask 8: 0 / 3