bool wgraph::get(FILE* f) {
// Get graph from f.
if (fscanf(f,"%d%d",&N,&M) != 2) return false;
delete [] firstedge; delete [] edges;
firstedge = new edge[N+1]; edges = new wgedge[M+2];
n = N; m = 1;
for (int i = 1; i <= 2*M; i++) {
// each edge appears twice in input
if (!getedge(m,f)) break;
if (edges[m].l > n || edges[m].r > n)
fatal("wgraph::get: out of range vertex number");
if (edges[m].l < edges[m].r) {
if (m > M) fatal("wgraph::get: edge mismatch");
m++;
}
}
m--; bldadj();
return true;
}
// Input graph. Allocate space only if necessary.
bool digraph::getGraph(istream & is) {
int nuN, nuM;
vertex u,v;
is >> nuN >> nuM;
if (nuN > mN || nuM > mM) {
fSpace();
mN = nuN;
mM = nuM;
mSpace();
}
N = nuN;
M = nuM;
edge e = 1;
while (e <= M) {
if (!getEdge(is,e)) return false;
}
bldadj();
return true;
}
void wgraph::esort() {
// Sort the edges by cost.
hsort(); bldadj();
}