Ural 1019 Line Painting (Line segment tree), ural1019

Ural 1019 Line Painting (Line segment tree), ural1019

Link: ural 1019 Line Painting

A 0 ~ The 1e9 interval is white at first, and now N operations are performed. Each time a color is set in the interval graph. Finally, the longest consecutive white interval is asked.

Solution: Merge the line segment tree intervals. Each node maintains an interval, which is classic. Note that the coordinates must be discretization, but 0 and 1e9 must be put in.

#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int maxn = 10005;const int INF = 0x3f3f3f3f;#define lson(x) ((x)<<1)#define rson(x) (((x)<<1)|1)struct pii {    int len, pos;    pii (int len = 0, int pos = 0) {        this->len = len;        this->pos = pos;    }    friend bool operator < (const pii& a, const pii& b) {        if (a.len != b.len)            return a.len < b.len;        return a.pos > b.pos;    }}s[maxn << 2];int N, M, pos[maxn], cnt = 0;int lc[maxn << 2], rc[maxn << 2], L[maxn << 2], R[maxn << 2], set[maxn << 2];inline int length(int u) {    return pos[rc[u] + 1] - pos[lc[u]];}inline void maintain(int u, int w) {    set[u] = w;    if (w) {        L[u] = R[u] = length(u);        s[u] = pii(R[u], pos[lc[u]]);    } else {        L[u] = R[u] = 0;        s[u] = pii(0, INF);    }}inline void pushup(int u) {    pii cur (L[rson(u)] + R[lson(u)], pos[lc[rson(u)]] - R[lson(u)]);    s[u] = max(max(s[lson(u)], s[rson(u)]), cur);    L[u] = L[lson(u)] + (L[lson(u)] == length(lson(u)) ? L[rson(u)] : 0);    R[u] = R[rson(u)] + (R[rson(u)] == length(rson(u)) ? R[lson(u)] : 0);    //printf("%d %d:%d %d!\n", lc[u], rc[u], s[u].pos, s[u].pos + s[u].len);}inline void pushdown(int u) {    if (set[u] != -1) {        maintain(lson(u), set[u]);        maintain(rson(u), set[u]);        set[u] = -1;    }}void build(int u, int l, int r) {    lc[u] = l; rc[u] = r;    set[u] = -1;    if (l == r) {        L[u] = R[u] = length(u);        s[u] = pii(R[u], pos[lc[u]]);        return;    }    int mid = (lc[u] + rc[u]) >> 1;    build(lson(u), l, mid);    build(rson(u), mid+1, r);    pushup(u);}void modify(int u, int l, int r, int w) {    if (l <= lc[u] && rc[u] <= r) {        maintain(u, w);        return;    }    pushdown(u);    int mid = (lc[u] + rc[u]) >> 1;    if (l <= mid)        modify(lson(u), l, r, w);    if (r > mid)        modify(rson(u), l, r, w);    pushup(u);}pii query(int u, int l, int r) {    if (l <= lc[u] && rc[u] <= r)        return s[u];    pushdown(u);    int mid = (lc[u] + rc[u]) >> 1;    pii ret(0, INF);    if (l <= mid)        ret = max(ret, query(lson(u), l, r));    if (r > mid)        ret = max(ret, query(rson(u), l, r));    pushup(u);    return ret;}struct Seg {    int l, r;    char op[5];    void read() { scanf("%d%d%s", &l, &r, op);}}q[maxn];int find (int x) {    return lower_bound(pos, pos + M, x) - pos;}void init () {    int n = 0;    for (int i = 1; i <= N; i++) {        q[i].read();        pos[i*2-1] = q[i].l;        pos[i*2] = q[i].r;    }    sort(pos + 1, pos + 1 + N * 2);    M = unique(pos + 1, pos + 1 + N * 2) - (pos+1);    pos[0] = 0;    pos[M + 1] = 1e9;    build(1, 0, M);}int main () {    while (scanf("%d", &N) == 1) {        init();        for (int i = 1; i <= N; i++) {            modify(1, find(q[i].l), find(q[i].r)-1, q[i].op[0] == 'w' ? 1 : 0);        }        printf("%d %d\n", s[1].pos, s[1].pos + s[1].len);    }    return 0;}

Pascal Line Segment tree line segment dyeing problem

This is ural 1019.
I seem to be violent after discretization ...... You can't remember. Check the code.
Program ural_p1019; // B = true, w = false
Type
Topt = record
St, en: longint;
P: boolean;
End;
Var tx, x: array [0 .. 10002] of longint;
Opt: array [1 .. 5000] of Topt;
Seg: array [1 .. 10002] of boolean;
K, st, en, m, I, j, ans, ansl, ansr: longint;
Ch: char;

Procedure init;
Begin
Assign(input,'input.txt '); reset (input );
Readln (m );
For I: = 1 to m do with opt [I] do begin
Read (st, en );
Read (ch );
Readln (ch );
P: = ch = 'B ';
End;
End;

Procedure qsort (l, r: longint );
Var I, j, mid, t: longint;
Begin
I: = l; j: = r; mid: = tx [(l + r)> 1];
Repeat
While tx [I] <mid do inc (I );
While tx [j]> mid do dec (j );
If I <= j then begin
T: = tx [I]; tx [I]: = tx [j]; tx [j]: = t;
Inc (I); dec (j );
End;
Until I> j;
If l <j then qsort (l, j );
If I <r then qsort (I, r );
End;

Procedure main;
Begin
Tx [0]: = 2;
Tx [1]: = 0;
Tx [2]: = 1000000000;
For I: = 1 to m do with opt [I] do begin
Inc (tx [0]);
Tx [tx [0]: = st;
Inc (tx [0]);
Tx [tx [0]: = en;
End;
Qsort (1, tx [0]);
For I: = 1 to tx [0] do if (x [0] = 0) or (x [x [0] <> tx [I]) then begin
Inc (x [0]);
X [x [0]: = tx [I];
End;
For I: = 1 to m do with opt [I] do begin
K: = 1;
While x [k] <st do inc (k );
While x [k] <en do begin
Seg [k]: = p;
Inc (k );
End;
End;
K: =... the remaining full text>