HDU - 6579 Operation【線性基】

題目鏈接

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這道題和$CodeForces - 1100F - Ivan and Burgers$這道題是一樣的，唯一的區別就是這道題強制在線。

還有啊TAT，題目說的是$mod\ n + 1$不是$mod\ (n + 1)$嗚嗚嗚

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
inline int read()
{
    int x = 0, f = 1; char c = getchar();
    while(c < '0' || c > '9') { if(c == '-') f = -f; c = getchar(); }
    while(c >= '0' && c <= '9') { x = x * 10 + c - '0'; c = getchar(); }
    return x * f;
}

const int maxN = 1000006;
const int maxBit = 31;

int n, m;
int p[maxN][maxBit];
int pos[maxN][maxBit];

void add(int x, int r)
{
    int id = r;
    for(int i = maxBit - 1; i >= 0; -- i ) p[r][i] = p[r - 1][i], pos[r][i] = pos[r - 1][i];
    for(int i = maxBit - 1; i >= 0; -- i )
    {
        if(x >> i & 1)
        {
            if(!p[r][i]) { p[r][i] = x; pos[r][i] = id; break; }
            if(pos[r][i] < id) { swap(p[r][i], x); swap(pos[r][i], id); }
            x ^= p[r][i];
        }
    }
}

int main()
{
    int TAT; TAT = read();
    while(TAT -- )
    {
        n = read(); m = read();
        for(int i = 1; i <= n; ++ i )
        {
            int x; x = read();
            add(x, i);
        }
        int lastans = 0;
        while(m -- )
        {
            int op; op = read();
            if(op) // 添加
            {
                int x = read();
                add(x ^ lastans, ++n);
            }
            else
            {
                int l, r; l = read(); r = read();
                l = (l ^ lastans) % n + 1;
                r = (r ^ lastans) % n + 1;
                if(l > r) swap(l, r);
                lastans = 0;
                for(int i = maxBit - 1; i >= 0; -- i )
                {
                    if(pos[r][i] >= l)
                        lastans = max(lastans, lastans ^ p[r][i]);
                }
                cout << lastans << endl;
            }
        }
    }
    return 0;
}