Cod sursa(job #290245)

Utilizator snaked31Stanica Andrei snaked31 Data 27 martie 2009 17:58:50
Problema Range minimum query Scor 90
Compilator cpp Status done
Runda Arhiva educationala Marime 0.99 kb
#include <stdio.h>

#define nm 100010
#define mm 18

int v[nm], log2[nm];
int a[nm][mm];
int n, m, i, x, y, j;

inline int mn (int a, int b) { return (a < b ? a : b); }


int rmq(int x, int y)

{
	int z = (y-x+1);
	int k = log2[z];

	return (mn ( v[a[x][k]], v[a[y-(1 << k)+1][k]] ));
}


void read()

{
	scanf("%d %d ", &n, &m);

	for (i=1; i<=n; ++i)
	{
		scanf("%d ", &v[i]);
		a[i][0] = i;

	}

	log2[1] = 0;

	for (i=2; i<=n; ++i)
	{
		log2[i] = log2[i/2] + 1;
	}

	for (j=1; 1 << j <=n; ++j)
	{
		for (i=1; (i + (1 << j) - 1 )<=n; ++i)
		{
			if (v[a[i][j-1]] < v[a[i + (1 << (j-1))][j-1]])
				a[i][j] = a[i][j-1];
			else
				a[i][j] = a[i + (1 << (j-1))][j-1];
		}
	}

}


void solve()

{
	for (i=1; i<=m; ++i)
	{
		scanf("%d %d ", &x, &y);
		printf("%d\n", rmq(x, y));
	}

}


void write()

{

}


int main()

{
	freopen("rmq.in", "r", stdin);
	freopen("rmq.out","w",stdout);

	read();
	solve();
	write();


	return 0;
}