Codeforces 551 E

E - GukiZ and GukiZiana

思路：分块， 块内二分

代码：

#pragma GCC optimize(2)
#pragma GCC optimize(3)
#pragma GCC optimize(4)
#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pi acos(-1.0)
#define LL long long
//#define mp make_pair
#define pb push_back
#define ls rt<<1, l, m
#define rs rt<<1|1, m+1, r
#define ULL unsigned LL
#define pll pair<LL, LL>
#define pli pair<LL, int>
#define pii pair<int, int>
#define piii pair<pii, int>
#define mem(a, b) memset(a, b, sizeof(a))
#define fio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define fopen freopen("in.txt", "r", stdin);freopen("out.txt", "w", stout);
//head

const int N = 5e5 + 10, M = 750;
const int INF = 0x3f3f3f3f;
int bl[N], blo, n;
LL tmp[M], a[N];
vector<pii> block[M];
void reset(int x) {
    block[x].clear();
    for (int i = (x-1)*blo + 1; i <= min(x*blo, n); i++) block[x].pb({a[i], i});
    sort(block[x].begin(), block[x].end());
}
void update(int l, int r, int x) {
    if(bl[l] == bl[r]) {
        for (int i = l; i <= r; i++) a[i] += x;
        reset(bl[l]);
        return ;
    }
    for (int i = l; i <= bl[l]*blo; i++) a[i] += x;
    reset(bl[l]);
    for (int i = bl[l]+1; i <= bl[r]-1; i++) tmp[i] += x;
    for (int i = (bl[r]-1)*blo+1; i <= r; i++) a[i] += x;
    reset(bl[r]);
}

int query(int x) {
    int l = -1, r = -1;
    for (int i = 1; i <= bl[n]; i++) {
        LL t = x - tmp[i];
        auto it = lower_bound(block[i].begin(), block[i].end(), pii{t, 0});
        if(it != block[i].end() && (*it).fi == t) {
            if(l == -1) l = r = (*it).se;
            else r = (*it).se;
        }
        it = upper_bound(block[i].begin(), block[i].end(), pii{t, INF});
        it--;
        if((*it).fi == t) {
            if(l == -1) l = r = (*it).se;
            else r = (*it).se;
        }
    }
    if(l == -1) return -1;
    else return r - l;
}
int main() {
    int q, ty, l, r, x;
    scanf("%d %d", &n, &q);
    blo = sqrt(n);
    for (int i = 1; i <= n; i++) scanf("%lld", &a[i]);
    for (int i = 1; i <= n; i++) bl[i] = (i-1)/blo + 1;
    for (int i = 1; i <= n; i++) block[bl[i]].pb({a[i], i});
    for (int i = 1; i <= bl[n]; i++) sort(block[i].begin(), block[i].end());
    while(q--) {
        scanf("%d", &ty);
        if(ty == 1) {
            scanf("%d %d %d", &l, &r, &x);
            update(l, r, x);
        }
        else {
            scanf("%d", &x);
            printf("%d
", query(x));
        }
    }
    return 0;
}