Submission #1125634

#	Time	Username	Problem	Language	Result	Execution time	Memory
1125634		baoheyhey	K blocks (IZhO14_blocks)	C++17	0 / 100	26 ms	41544 KiB

blocks

#include<bits/stdc++.h>
#define ll long long
#define FOR(i, l, r) for(int i = (l), _r = r; i <= _r; ++i)
#define FOD(i, l, r) for(int i = (l), _r = r; i >= _r; --i)
#define pb push_back
#define ALL(a) a.begin(), a.end()
#define el "\n"
#define bit(a, x) (a >> x & 1)
#define X first
#define Y second
#define TIME (1.0 * clock() / CLOCKS_PER_SEC)
#define cntbit(x) __builtin_popcountll(x)
#define uni(a) sort(ALL(a)), a.resize(unique(ALL(a)) - a.begin())
#define sz(a) a.size()

using namespace std;

typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;

const int maxn = 1e5 + 5;

int dp[maxn][105];
int n, a[maxn], k;

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    #define task "task"
    if(fopen(task".inp", "r")){
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    cin >> n >> k;
    FOR(i, 1, n) cin >> a[i];
    memset(dp, 0x3f, sizeof(dp));
    dp[0][1] = 0;
    FOR(i, 1, n) dp[i][1] = max(dp[i - 1][1], a[i]);
    FOR(i, 2, k){
        stack<pii> st;
        FOR(j, i, n){
            int minn = dp[j - 1][i - 1];
            while(sz(st) && a[st.top().Y] <= a[j]){
                minn = st.top().X;
                st.pop();
            }
            dp[j][i] = min(dp[(sz(st) ? st.top().Y : 0)][i], minn + a[j]);
            st.push({minn, j});
        }
    }
    cout << dp[n][k];
    cerr << "Time elapsed: " << TIME << " s" << el;
}

Compilation message (stderr)

blocks.cpp: In function 'int main()':
blocks.cpp:33:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
blocks.cpp:34:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   34 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 14
• Subtask 2: 0 / 18
• Subtask 3: 0 / 21
• Subtask 4: 0 / 47