No entiendo los posibles recorridos de gráficos cíclicos, ¿por qué hay una conexión entre el nodo de origen y el de destino en el gráfico?

i) DFS, si se visita un nodo, devolvemos falso

ii) BFS, si se visita un nodo, continuamos (en el bucle)

código de ejemplo (de https://structy.net/problems/undirected-path ):

 const undirectedPath = (edges, nodeA, nodeB) => { const graph = buildGraph(edges); return hasPath(graph, nodeA, nodeB, new Set()); } // BFS const hasPath = (graph, src, dst, visited) => { const queue = [src]; while(queue.length > 0){ const current = queue.shift(); if(current === dst) return true; // if it's DFS, do not "continue", instead "return false" - why? if(visited.has(current)) continue; visited.add(current); for(let neighbor of graph[current]){ queue.push(neighbor); } } return false; } const buildGraph = (edges) => { const graph = {}; for(let edge of edges){ const[a, b] = edge; if(!(a in graph)) graph [a] = []; if(!(b in graph)) graph [b] = []; graph[a].push(b); graph[b].push(a); } return graph; } const edges = [ ['i', 'j'], ['k', 'i'], ['m', 'k'], ['k', 'l'], ['o', 'n'] ]; undirectedPath(edges, 'j', 'm'); // -> true