Cod sursa(job #639922)

Utilizator swift90Ionut Bogdanescu swift90 Data 24 noiembrie 2011 13:15:51
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1 kb
#include<cstdio>
#include<fstream>
using namespace std;
int nr[18][100100],log[100100];
inline int min(int a,int b){
	return a<b?a:b;
}
int main(){
	freopen("rmq.in","r",stdin);
	ofstream g("rmq.out");
	int n,m,i,j,x,y,d;
	char s[100];
	fgets(s,100,stdin);
	for(i=0,n=0;'0'<=s[i] && s[i]<='9';++i)
		n=n*10+s[i]-'0';
	while(!('0'<=s[i] && s[i]<='9'))
		++i;
	for(m=0;'0'<=s[i] && s[i]<='9';++i)
		m=m*10+s[i]-'0';
	for(i=2;i<=n;++i)
		log[i]=log[i>>1]+1;
	for(i=1;i<=n;++i){
		fgets(s,100,stdin);
		for(j=0,x=0;'0'<=s[j] && s[j]<='9';++j)
			x=x*10+s[j]-'0';
		nr[0][i]=x;
	}
	for(j=1;(1<<j)<=n+1;++j){
		for(i=1;i+(1<<j)<=n+1;++i){
			nr[j][i]=min(nr[j-1][i],nr[j-1][i+(1<<(j-1))]);
		}
	}
	for(i=0;i<m;++i){
		fgets(s,100,stdin);
		for(j=0,x=0;'0'<=s[j] && s[j]<='9';++j)
			x=x*10+s[j]-'0';
		while(!('0'<=s[j] && s[j]<='9'))
			++j;
		for(y=0;'0'<=s[j] && s[j]<='9';++j)
			y=y*10+s[j]-'0';
		d=y-x+1;
		j=log[d];
		d-=(1<<j);
		g<<min(nr[j][x],nr[j][x+d])<<'\n';
	}
	
	fclose(stdin);
	fclose(stdout);
	return 0;
}