Submission #39381

#	Time	Username	Problem	Language	Result	Execution time	Memory
39381		Extazy	Money (IZhO17_money)	C++14	25 / 100	3 ms	18780 KiB

money

#include <bits/stdc++.h>
#define endl '\n'
#define prev kjlahjkghakj
#define left iljhghakjja
#define right lkhljahjkajhahja

using namespace std;

const int N = 1000007;

int n,a[N];
bool used[N];
int state[N];
int left[N],right[N];

multiset < int >::iterator prev(multiset < int >::iterator it) {
    --it;
    return it;
}

bool are_consecutive(multiset < int > &s, int v1, int v2) {
    if(v1==v2) return true;
    return *prev(s.lower_bound(v2))==v1; 
}

int recurse(int pos) {
    if(pos<1) return 0;
    if(used[pos]) return state[pos];

    used[pos]=true;

    int i,ans=recurse(pos-1)+1;
    multiset < int > s;
    int leftmost=pos,rightmost=pos;

    for(i=1;i<=pos;i++) s.insert(a[i]);
    for(i=pos-1;i>=1;i--) {
        if(!are_consecutive(s,a[i],a[i+1])) break;
        if(a[i]<a[i+1]) {
            if(a[i+1]!=a[pos]) {
                leftmost=min(leftmost,left[a[i+1]]);
                rightmost=max(rightmost,right[a[i+1]]);
            }
        }
        if(leftmost<i || rightmost>pos) continue;
        ans=min(ans,1+recurse(i-1));
    }

    return state[pos]=ans;
}

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

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

    printf("%d\n", recurse(n));

    return 0;
}

Compilation message (stderr)

money.cpp: In function 'int main()':
money.cpp:57:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
                    ^
money.cpp:59:27: 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: 0 / 20
• Subtask 4: 0 / 55