Submission #870750

#	Time	Username	Problem	Language	Result	Execution time	Memory
870750		tuannm	Arranging Shoes (IOI19_shoes)	C++17	Compilation error	0 ms	0 KiB

shoes

#include<bits/stdc++.h>
#define ii pair<int, int>
#define ll pair<long long, long long>
#define fi first
#define se second
#define pb push_back
using namespace std;
const int mod[2] = {1000000007, 998244353};
const int N = 2e5 + 1;
const string NAME = "";
const int lim = 2147483647;
//const unsigned int lim = 4294967295;
//const long long lim = 9223372036854775807;
//const unsigned long long lim = 18446744073709551615;
const int mset = 0x3f;
const double pi = acos(-1);
int n, a[N];
vector<int> q[2][N];
int perm[N];
long long tree[4 * N];
bool used[N];

void update(int s, int l, int r, int x, int y){
    if(x < l || x > r)
        return;
    if(l == r){
        tree[s] += y;
        return;
    }
    int mid = (l + r) / 2;
    update(2 * s, l, mid, x, y);
    update(2 * s + 1, mid + 1, r, x, y);
    tree[s] = tree[2 * s] + tree[2 * s + 1];
}

long long get(int s, int l, int r, int u, int v){
    if(l > v || r < u)
        return 0;
    if(l >= u && r <= v)
        return tree[s];
    int mid = (l + r) / 2;
    return get(2 * s, l, mid, u, v) + get(2 * s + 1, mid + 1, r, u, v);
}

void inp(){
    cin >> n;
    for(int i = 1; i <= 2 * n; ++i){
        cin >> a[i];
        if(a[i] > 0)
            q[1][a[i]].pb(i);
        else q[0][-a[i]].pb(i);
    }
    for(int i = 1; i <= n; ++i){
        reverse(q[0][i].begin(), q[0][i].end());
        reverse(q[1][i].begin(), q[1][i].end());
    }
}

void solve(){
    int cnt = 0;
    for(int i = 1; i <= 2 * n; ++i){
        if(used[i])
            continue;
        if(a[i] > 0){
            int t0 = q[0][a[i]].back();
            int t1 = q[1][a[i]].back();
            q[1][a[i]].pop_back();
            q[0][a[i]].pop_back();
            used[t0] = true;
            used[t1] = true;
            perm[t0] = ++cnt;
            perm[t1] = ++cnt;
        }
        else{
            int t0 = q[0][-a[i]].back();
            int t1 = q[1][-a[i]].back();
            q[1][-a[i]].pop_back();
            q[0][-a[i]].pop_back();
            used[t0] = true;
            used[t1] = true;
            perm[t0] = ++cnt;
            perm[t1] = ++cnt;
        }
    }
    long long ans = 0;
    for(int i = 1; i <= 2 * n; ++i){
        ans += get(1, 1, 2 * n, perm[i] + 1, 2 * n);
        update(1, 1, 2 * n, perm[i], 1);
    }
    cout << ans;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    if(fopen((NAME + ".inp").c_str(), "r")){
        freopen((NAME + ".inp").c_str(), "r", stdin);
        freopen((NAME + ".out").c_str(), "w", stdout);
    }

    inp();
    solve();
}

Compilation message (stderr)

shoes.cpp: In function 'int main()':
shoes.cpp:99:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   99 |         freopen((NAME + ".inp").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
shoes.cpp:100:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  100 |         freopen((NAME + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccDMYmxs.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccGgQfPq.o:shoes.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/ccDMYmxs.o: in function `main':
grader.cpp:(.text.startup+0x2a8): undefined reference to `count_swaps(std::vector<int, std::allocator<int> >)'
collect2: error: ld returned 1 exit status