#include <stdio.h>

void leeAlturas( FILE *entrada, int size, float *array )
    {
    int i;
    for( i = 0; i < size; i++ )
        fscanf( entrada, "%f", &( array[i] ) );
    }

void escribeSalida( FILE *salida, int size, float *array )
    {
    int *intervalos = new int[size];
    
    int i, picoInicio = -1, countPicos = 0;
    for( i = 1; i < size; i++ )
        if( array[i] < array[i-1] )
            {
            if( picoInicio > -1 )
                {
                intervalos[2*countPicos] = picoInicio+1;
                intervalos[2*countPicos+1] = i;
                countPicos++;
                }
            picoInicio = -1;
            }
        else if( array[i] > array[i-1] )
             picoInicio = i;
    fprintf( salida, "%d\n", countPicos );
    for( i = 0; i < countPicos; i++ )
        fprintf( salida, "%d %d ", intervalos[2*i], intervalos[2*i+1] );
    delete[] intervalos;
    }

int main()
    {
    int size;
    float *array;
    FILE *entrada = fopen( "input.txt", "rt" );
    fscanf( entrada, "%d", &size );
    array = new float[size];
    leeAlturas( entrada, size, array );
    fclose( entrada );
    FILE *salida = fopen( "output.txt", "wt" );
    escribeSalida( salida, size, array );
    fclose( salida );
    delete[] array;
    return 0;
    }