Submission #44286

#	Time	Username	Problem	Language	Result	Execution time	Memory
44286		Extazy	Money (IZhO17_money)	C++17	100 / 100	283 ms	152484 KiB

money

#include <bits/stdc++.h>
#define endl '\n'

using namespace std;

const int N = 1000007;

int n,a[N],it[N],ans;

void update(int pos, int val) {
    for(;pos<N;pos+=pos&(-pos)) it[pos]+=val;
}

int query(int pos) {
    int ans=0;
    for(;pos>=1;pos-=pos&(-pos)) ans+=it[pos];
    return ans;
}

int query(int l, int r) {
    return l>r ? 0 : query(r)-query(l-1);
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int i,j;

    scanf("%d", &n);
    for(i=1;i<=n;i++) {
        scanf("%d", &a[i]);
    }

    for(i=1;i<=n;) {
        ++ans;

        j=i;
        while(j+1<=n && a[j]<=a[j+1] && query(a[i]+1,a[j+1]-1)==0) {
            ++j;
        }

        for(;i<=j;i++) {
            update(a[i],1);
        }
    }

    printf("%d\n", ans);
    
    return 0;
}

Compilation message (stderr)

money.cpp: In function 'int main()':
money.cpp:29:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
money.cpp:31:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &a[i]);
         ~~~~~^~~~~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 16 / 16
• Subtask 3: 20 / 20
• Subtask 4: 55 / 55