UVA 10004

#include <stdio.h>#include <string.h>#include <stdlib.h>int v;int q[20000];int map[300][300], vis[300], val[300];void bfs( int x ){int front, rear, a = 0, nx, next;front = rear = 0;q[front++] = x;val[x] = 1;vis[x] = 1;while( front > rear ){nx = q[rear++];if( val[nx] == 1 )a = 0;elsea = 1;for( next = 0; next < v; next++ )if( map[nx][next] && !vis[next] ) {val[next] = a;q[front++] = next;vis[next] = 1;}}}int main(){int flag, e, i, x[300], y[300];while( scanf( "%d",  &v) && v ){memset( map, 0, sizeof(map) );memset( vis, 0, sizeof(vis) );scanf( "%d", &e );for( i = 0; i < e; i++ ){scanf( "%d%d", &x[i], &y[i] );map[x[i]][y[i]] = map[y[i]][x[i]] = 1;}bfs( x[0] );flag = 1;for( i = 0; i < e; i++ )if( val[x[i]] == val[y[i]] ){flag = 0;break;}if( flag )printf( "BICOLORABLE.\n" );elseprintf( "NOT BICOLORABLE.\n" );}return 0;}