Nbut 1457 Sona (Mo team algorithm)

Main topic:

Three times the number of occurrences of a number in a range

Thinking Analysis:

It's really hard to get past the water, all sorts of optimizations.

The map cannot be used and the lowerbound will be processed first after discretization.

Optimize the input.

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The time card is very tight.

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The topic is directly used by the team water.

If you time out, it's best to try the top three optimizations.

#include <cstdio> #include <iostream> #include <cstring> #include <algorithm> #include <map > #include <cmath> #define MAXN 100005using namespace Std;typedef long long ll;int app[maxn];int pos[maxn];int sav    E[maxn];int x[maxn];map<int,int>mymap;struct foo{int l,r,index;    LL ans;        BOOL operator < (const foo &AMP;CMP) const {if (POS[L]==POS[CMP.L]) return r<cmp.r;    Return pos[l]<pos[cmp.l];    }}q[maxn];int n;inline void scanf_ (int &num) {char in;    BOOL Neg=false;    while ((In=getchar () > ' 9 ' | | in< ' 0 ') && in!= '-');        if (in== '-') {neg=true;    while (In=getchar ()) > ' 9 ' | | in< ' 0 ');    } num=in-' 0 ';    while (In=getchar (), in>= ' 0 ' &&in<= ' 9 ') num*=10,num+=in-' 0 '; if (neg) num=0-num;} BOOL cmp_id (const foo &a,const foo &b) {return a.index<b.index;}    int sz;void Modify (int p,ll &ans,int add) {ans-= (LL) app[x[p]]*app[x[p]]*app[x[p]]; ApP[x[p]]+=add; ans+= (LL) app[x[p]]*app[x[p]]*app[x[p]];}        int main () {while (scanf ("%d", &n)!=eof) {memset (app,0,sizeof app);        int SIZE = (int) sqrt (n*1.0);            for (int i=1;i<=n;i++) {scanf_ (save[i]);            X[i]=save[i];        pos[i]= (i-1)/size+1;        } int m;        Scanf_ (m);            for (int i=0;i<m;i++) {scanf_ (Q[I].L);            Scanf_ (Q[I].R);        Q[i].index=i;        } sort (save+1,save+n+1);        Sz=unique (save+1,save+n+1)-save;        for (int i=1;i<=n;i++) {X[i] = Lower_bound (save+1,save+sz,x[i])-save;        } sort (q,q+m);        LL ans=0; for (int i=0,l=1,r=0;i<m;i++) {if (R&LT;Q[I].R) {for (r=r+1;r<=q[i].r;r++                ) modify (r,ans,1);            r--; } if (R&GT;Q[I].R) {for (; r>q[i].r;r--) {mOdify (r,ans,-1); }} if (L&LT;Q[I].L) {for (; l<q[i].l;l++) Modify (L,an            S,-1);                } if (L&GT;Q[I].L) {for (l=l-1;l>=q[i].l;l--) modify (l,ans,1);            l++;                } if (Q[I].L==Q[I].R) {Q[i].ans=1;            Continue        } Q[i].ans=ans;        } sort (q,q+m,cmp_id);    for (int i=0;i<m;i++) printf ("%i64d\n", Q[i].ans); } return 0;}

Nbut 1457 Sona (Mo team algorithm)