BZOJ 1699

标准RMQ，第一次写贴下代码，加入了IO优化

#include <iostream>#include <cstdio>#include <cstring>#include <string>#include <ctime>#include <cmath>#include <vector>#include <deque>#include <algorithm>#include <list>#include <map>#include <set>#include <queue>#include <stack>#define REP(i,n) for(int i=0;i<(n);i++)#define REP1(i,n) for(int i=1;i<=(n);i++)#define FOR(i,a,b) for (int i=(a);i<=(b);i++)#define CLR(x,n) memset(x,n,sizeof(x))#define PN printf("\n")#define read(x) scanf("%d",&x)#define read2(x,y) scanf("%d%d",&x,&y)#define read3(x,y,z) scanf("%d%d%d",&x,&y,&z)#define write(x) printf("%d",x)#define write1(x) printf("%d ",x)#define writeln(x) printf("%d\n",x)#define write2(x,y) printf("%d %d",x,y)#define writeln2(x,y) printf("%d %d\n",x,y)#define write3(x,y,z) printf("%d %d %d",x,y,z)#define writeln3(x,y,z) printf("%d %d %d\n",x,y,z)using namespace std;inline int readint(){    int ans=0;char c;do c=getchar();while (!(c<='9'&& c>='0'));    do{        ans=ans*10+c-'0';        c=getchar();}    while (c<='9'&& c>='0');    return ans;}char buf[20];int d1[50100][20],d2[50100][20];    inline void writeint(int i){    int p=0;    if (!i){p++;buf[0]='0';}    else while (i){        buf[p++]=i%10+'0';        i/=10;    }    for (int j=p-1;j>=0;j--)putchar(buf[j]);}int n,q;void RMQ_init1(){    for (int j=1;(1<<j)<=n;j++)    for (int i=1;i+(1<<j)-1<=n;i++)    d1[i][j]=min(d1[i][j-1],d1[i+( 1<<(j-1) )][j-1]);    //REP1(i,n){REP(j,4)write1(d1[i][j]);PN;}}void RMQ_init2(){    for (int j=1;(1<<j)<=n;j++)    for (int i=1;i+(1<<j)-1<=n;i++)    d2[i][j]=max(d2[i][j-1],d2[i+( 1<<(j-1) )][j-1]);    //REP1(i,n){REP(j,4)write1(d2[i][j]);PN;}}int RMQ_find1(int l,int r){    int k=0;    while ( (1<<k)<=r-l+1)k++;--k;    return min(d1[l][k],d1[r-(1<<k)+1][k]);}int RMQ_find2(int l,int r){    int k=0;    while ( (1<<k)<=r-l+1)k++;--k;    return max(d2[l][k],d2[r-(1<<k)+1][k]);}int main(){    n=readint();q=readint();    REP1(i,n){d1[i][0]=readint();d2[i][0]=d1[i][0];}    RMQ_init1();RMQ_init2();    int l,r;    REP(i,q){        l=readint();r=readint();        //cout<<RMQ_find2(l,r) -RMQ_find1(l,r)<<endl;        writeint(RMQ_find2(l,r) -RMQ_find1(l,r));PN;    }    system("pause");    return 0;}