Submission #220350

#	Time	Username	Problem	Language	Result	Execution time	Memory
220350		Matteo_Verz	XORanges (eJOI19_xoranges)	C++11	100 / 100	149 ms	8788 KiB

xoranges

/*
                `-/oo+/-   ``
              .oyhhhhhhyo.`od
             +hhhhyyoooos. h/
            +hhyso++oosy- /s
           .yoooossyyo:``-y`
            ..----.` ``.-/+:.`
                   `````..-::/.
                  `..```.-::///`
                 `-.....--::::/:
                `.......--::////:
               `...`....---:::://:
             `......``..--:::::///:`
            `---.......--:::::////+/`
            ----------::::::/::///++:
            ----:---:::::///////////:`
            .----::::::////////////:-`
            `----::::::::::/::::::::-
             `.-----:::::::::::::::-
               ...----:::::::::/:-`
                 `.---::/+osss+:`
                   ``.:://///-.
*/
#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <cmath>

using namespace std;

const int INF = 2e9;
const int N = 2e5;

int n, q;
int v[5 + N];

class AIB{
private:
    int a[5 + N];

    int lsb(int i){
        return (i & (-i));
    }

public:
    void Build(int pos, int val){
        for(int i = pos; i <= n; i += lsb(i))
            a[i] = a[i] ^ val;
    }

    void Update(int pos, int val){
        for(int i = pos; i <= n; i += lsb(i))
            a[i] = a[i] ^ v[pos] ^ val;
        v[pos] = val;
    }

    int Query(int pos){
        int s(0);
        for(int i = pos; i >= 1; i -= lsb(i))
            s ^= a[i];

        return s;
    }
};
AIB FenwOdd, FenwEven;

int main() {
#ifdef CP
    freopen("xoranges.in", "r", stdin);
    freopen("xoranges.out", "w", stdout);
#endif // CP

    scanf("%d%d", &n, &q);
    for(int i = 1; i <= n; i++){
        scanf("%d", &v[i]);
        if(i & 1) FenwOdd.Build(i, v[i]);
        else FenwEven.Build(i, v[i]);
    }

    while(q--){
        int t, x, y;
        scanf("%d%d%d", &t, &x, &y);
        if(t == 1){
            if(x & 1) FenwOdd.Update(x, y);
            else FenwEven.Update(x, y);
        } else{
            if((x - y + 1) & 1){
                if(y & 1) printf("%d\n", FenwOdd.Query(y) ^ FenwOdd.Query(x - 2));
                else printf("%d\n", FenwEven.Query(y) ^ FenwEven.Query(x - 2));
            } else printf("0\n");
        }
    }
    return 0;
}

Compilation message (stderr)

xoranges.cpp: In function 'int main()':
xoranges.cpp:80:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d", &n, &q);
     ~~~~~^~~~~~~~~~~~~~~~
xoranges.cpp:82:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &v[i]);
         ~~~~~^~~~~~~~~~~~~
xoranges.cpp:89:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%d", &t, &x, &y);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~

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