Submission #1301392

#	Time	Username	Problem	Language	Result	Execution time	Memory
1301392		tamir1	Obstacles for a Llama (IOI25_obstacles)	C++20	Compilation error	0 ms	0 KiB

obstacles

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

static int N, M;
static vector<int> Tval, Hval;
static vector<int> c;
static vector<int> b;

// Segment trees
static vector<int> seg_min, seg_max;

// Build segment trees
void build_seg_min(int node, int l, int r) {
    if (l == r) {
        seg_min[node] = Hval[l];
        return;
    }
    int mid = (l + r) / 2;
    build_seg_min(2*node, l, mid);
    build_seg_min(2*node+1, mid+1, r);
    seg_min[node] = min(seg_min[2*node], seg_min[2*node+1]);
}

void build_seg_max(int node, int l, int r) {
    if (l == r) {
        seg_max[node] = Hval[l];
        return;
    }
    int mid = (l + r) / 2;
    build_seg_max(2*node, l, mid);
    build_seg_max(2*node+1, mid+1, r);
    seg_max[node] = max(seg_max[2*node], seg_max[2*node+1]);
}

// Query min in range [ql, qr]
int query_min(int node, int l, int r, int ql, int qr) {
    if (qr < l || r < ql) return INT_MAX;
    if (ql <= l && r <= qr) return seg_min[node];
    int mid = (l + r) / 2;
    return min(query_min(2*node, l, mid, ql, qr),
               query_min(2*node+1, mid+1, r, ql, qr));
}

// Query max in range [ql, qr]
int query_max(int node, int l, int r, int ql, int qr) {
    if (qr < l || r < ql) return INT_MIN;
    if (ql <= l && r <= qr) return seg_max[node];
    int mid = (l + r) / 2;
    return max(query_max(2*node, l, mid, ql, qr),
               query_max(2*node+1, mid+1, r, ql, qr));
}

// Wrappers to match your style
int call_min(int l, int r) {
    return query_min(1, 0, M-1, l, r);
}

int call_max(int l, int r) {
    return query_max(1, 0, M-1, l, r);
}

void initialize(vector<int> T, vector<int> H) {
    Tval = T; Hval = H;
    N = Tval.size(); M = Hval.size();

    int d = Tval[0]; 
    c.assign(M, 0); 
    b.assign(M, -1);

    for(int i = 0; i < M; i++) {
        if(Hval[i] >= d) c[i] = 1;
        else c[i] = 0;
    }

    vector<int> sum(M, 0);
    sum[0] = c[0];
    for(int i = 1; i < M; i++) sum[i] = sum[i-1] + c[i];

    vector<int> right(M), left(M);
    int last = M;
    for(int i = M-1; i >= 0; i--) {
        if(c[i] == 1) last = i;
        right[i] = last-1;
    }

    last = -1;
    for(int i = 0; i < M; i++) {
        if(c[i] == 1) last = i;
        left[i] = last+1;
    }

    // Initialize segment trees
    seg_min.assign(4*M, INT_MAX);
    seg_max.assign(4*M, INT_MIN);
    build_seg_min(1, 0, M-1);
    build_seg_max(1, 0, M-1);
}

bool can_reach(int L, int R, int S, int D) {
    bool st=false, en=false;
    if(S > D) swap(S,D);
    if(call_max(S,D)>=3) return false;
    
    int sad = left[S];
    int happy = right[S];
    
    if(call_min(sad, happy) == 0) st = true;

    sad = left[D];
    happy = right[D];
    if(call_min(sad, happy) == 0) en = true;

    if(st && en) return true;

    if(sum[D]-sum[S-1]==0) return true;

    return false;
}

Compilation message (stderr)

obstacles.cpp: In function 'bool can_reach(int, int, int, int)':
obstacles.cpp:105:21: warning: pointer to a function used in arithmetic [-Wpointer-arith]
  105 |     int sad = left[S];
      |                     ^
obstacles.cpp:105:21: error: invalid conversion from 'std::ios_base& (*)(std::ios_base&)' to 'int' [-fpermissive]
  105 |     int sad = left[S];
      |                     ^
      |                     |
      |                     std::ios_base& (*)(std::ios_base&)
obstacles.cpp:106:24: warning: pointer to a function used in arithmetic [-Wpointer-arith]
  106 |     int happy = right[S];
      |                        ^
obstacles.cpp:106:24: error: invalid conversion from 'std::ios_base& (*)(std::ios_base&)' to 'int' [-fpermissive]
  106 |     int happy = right[S];
      |                        ^
      |                        |
      |                        std::ios_base& (*)(std::ios_base&)
obstacles.cpp:110:17: warning: pointer to a function used in arithmetic [-Wpointer-arith]
  110 |     sad = left[D];
      |                 ^
obstacles.cpp:110:17: error: invalid conversion from 'std::ios_base& (*)(std::ios_base&)' to 'int' [-fpermissive]
  110 |     sad = left[D];
      |           ~~~~~~^
      |                 |
      |                 std::ios_base& (*)(std::ios_base&)
obstacles.cpp:111:20: warning: pointer to a function used in arithmetic [-Wpointer-arith]
  111 |     happy = right[D];
      |                    ^
obstacles.cpp:111:20: error: invalid conversion from 'std::ios_base& (*)(std::ios_base&)' to 'int' [-fpermissive]
  111 |     happy = right[D];
      |             ~~~~~~~^
      |                    |
      |                    std::ios_base& (*)(std::ios_base&)
obstacles.cpp:116:8: error: 'sum' was not declared in this scope
  116 |     if(sum[D]-sum[S-1]==0) return true;
      |        ^~~