Submission #639516

#	Time	Username	Problem	Language	Result	Execution time	Memory
639516		tade	Crayfish scrivener (IOI12_scrivener)	C++17	Compilation error	0 ms	0 KiB

scrivener

#include <bits/stdc++.h>
#define int long long

using namespace std;

struct trie_node
{
    int child[26];
    char letter;
    int depth;
    trie_node()
    {
        memset(child, -1, sizeof(child));
        depth = 0;
    }
};

int st[100005][22];
vector<trie_node> trie;
vector<int> cmds;
int node = 0;

void Init()
{
    trie.push_back(trie_node());
    trie[0].letter = '#';
    trie[0].depth = -1;
    cmds.push_back(0);
}

void TypeLetter(char L)
{
    int nxt = L - 'a';
    if(trie[node].child[nxt] == -1)
    {
        trie[node].child[nxt] = trie.size();
        trie.push_back(trie_node());
    }
    
    int parent = node;
    node = trie[node].child[nxt];
    trie[node].letter = L;
    trie[node].depth = trie[parent].depth + 1;

    st[node][0] = parent;
    for(int i = 1; i < 22; ++ i)
        st[node][i] = st[st[node][i - 1]][i - 1];
    cmds.push_back(node);
}

void UndoCommands(int U)
{
    node = cmds[cmds.size() - U - 1];
    cmds.push_back(node);
}

char GetLetter(int P)
{
    int jump_dist = trie[node].depth - P;
    int jump_node = node;
    for(int i = 0; i < 22 && jump_dist > 0; ++ i)
    {
        if(jump_dist & 1) jump_node = st[jump_node][i];
        jump_dist >>= 1;
    }
    return trie[jump_node].letter;
}

Compilation message (stderr)

/usr/bin/ld: /tmp/ccf9xo9T.o: in function `main':
grader.cpp:(.text.startup+0x15f): undefined reference to `UndoCommands(int)'
/usr/bin/ld: grader.cpp:(.text.startup+0x18b): undefined reference to `GetLetter(int)'
collect2: error: ld returned 1 exit status