Submission #930510

#	Time	Username	Problem	Language	Result	Execution time	Memory
930510		sleepntsheep	XORanges (eJOI19_xoranges)	C++17	100 / 100	97 ms	10324 KiB

xoranges

#include <stdio.h>

#define N 200000

int n, q;

struct st
{
    int t[N<<1];
    void upd(int p, int k)
    {
        for (t[p += n] = k; p >>= 1;) t[p] = t[p<<1] ^ t[p<<1|1];
    }

    int qry(int l, int r)
    {
        int z = 0;
        for (l += n, r += n; l < r; l >>= 1, r >>= 1)
        {
            if (l&1) z ^= t[l++];
            if (r&1) z ^= t[--r];
        }
        return z;
    }
} t[2];

int a[N];

int main()
{
    scanf("%d%d", &n, &q);
    for (int i = 0; i < n; ++i) scanf("%d", a+i), t[i&1].upd(i, a[i]);

    for (int op, x, y; q--;)
    {
        scanf("%d%d%d", &op, &x, &y);
        switch (op)
        {
            case 1:
                --x;
                t[x&1].upd(x, y);
                break;
            default:
                --x, --y;
                if ((y - x) & 1)
                {
                    puts("0");
                }
                else
                {
                    printf("%d\n", t[x&1].qry(x, y+1));
                }
                break;
        }
    }

    return 0;
}

Compilation message (stderr)

xoranges.cpp: In function 'int main()':
xoranges.cpp:31:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 |     scanf("%d%d", &n, &q);
      |     ~~~~~^~~~~~~~~~~~~~~~
xoranges.cpp:32:38: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |     for (int i = 0; i < n; ++i) scanf("%d", a+i), t[i&1].upd(i, a[i]);
      |                                 ~~~~~^~~~~~~~~~~
xoranges.cpp:36:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   36 |         scanf("%d%d%d", &op, &x, &y);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 25 / 25
• Subtask 4: 20 / 20
• Subtask 5: 25 / 25