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diff --git a/glpk-5.0/src/api/rdmcf.c b/glpk-5.0/src/api/rdmcf.c
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+/* rdmcf.c (read min-cost flow problem data in DIMACS format) */
+
+/***********************************************************************
+* This code is part of GLPK (GNU Linear Programming Kit).
+* Copyright (C) 2009-2016 Free Software Foundation, Inc.
+* Written by Andrew Makhorin <mao@gnu.org>.
+*
+* GLPK is free software: you can redistribute it and/or modify it
+* under the terms of the GNU General Public License as published by
+* the Free Software Foundation, either version 3 of the License, or
+* (at your option) any later version.
+*
+* GLPK is distributed in the hope that it will be useful, but WITHOUT
+* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
+* License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with GLPK. If not, see <http://www.gnu.org/licenses/>.
+***********************************************************************/
+
+#include "dimacs.h"
+#include "glpk.h"
+#include "misc.h"
+
+#define error dmx_error
+#define warning dmx_warning
+#define read_char dmx_read_char
+#define read_designator dmx_read_designator
+#define read_field dmx_read_field
+#define end_of_line dmx_end_of_line
+#define check_int dmx_check_int
+
+/***********************************************************************
+* NAME
+*
+* glp_read_mincost - read min-cost flow problem data in DIMACS format
+*
+* SYNOPSIS
+*
+* int glp_read_mincost(glp_graph *G, int v_rhs, int a_low, int a_cap,
+* int a_cost, const char *fname);
+*
+* DESCRIPTION
+*
+* The routine glp_read_mincost reads minimum cost flow problem data in
+* DIMACS format from a text file.
+*
+* RETURNS
+*
+* If the operation was successful, the routine returns zero. Otherwise
+* it prints an error message and returns non-zero. */
+
+int glp_read_mincost(glp_graph *G, int v_rhs, int a_low, int a_cap,
+ int a_cost, const char *fname)
+{ DMX _csa, *csa = &_csa;
+ glp_vertex *v;
+ glp_arc *a;
+ int i, j, k, nv, na, ret = 0;
+ double rhs, low, cap, cost;
+ char *flag = NULL;
+ if (v_rhs >= 0 && v_rhs > G->v_size - (int)sizeof(double))
+ xerror("glp_read_mincost: v_rhs = %d; invalid offset\n",
+ v_rhs);
+ if (a_low >= 0 && a_low > G->a_size - (int)sizeof(double))
+ xerror("glp_read_mincost: a_low = %d; invalid offset\n",
+ a_low);
+ if (a_cap >= 0 && a_cap > G->a_size - (int)sizeof(double))
+ xerror("glp_read_mincost: a_cap = %d; invalid offset\n",
+ a_cap);
+ if (a_cost >= 0 && a_cost > G->a_size - (int)sizeof(double))
+ xerror("glp_read_mincost: a_cost = %d; invalid offset\n",
+ a_cost);
+ glp_erase_graph(G, G->v_size, G->a_size);
+ if (setjmp(csa->jump))
+ { ret = 1;
+ goto done;
+ }
+ csa->fname = fname;
+ csa->fp = NULL;
+ csa->count = 0;
+ csa->c = '\n';
+ csa->field[0] = '\0';
+ csa->empty = csa->nonint = 0;
+ xprintf("Reading min-cost flow problem data from '%s'...\n",
+ fname);
+ csa->fp = glp_open(fname, "r");
+ if (csa->fp == NULL)
+ { xprintf("Unable to open '%s' - %s\n", fname, get_err_msg());
+ longjmp(csa->jump, 1);
+ }
+ /* read problem line */
+ read_designator(csa);
+ if (strcmp(csa->field, "p") != 0)
+ error(csa, "problem line missing or invalid");
+ read_field(csa);
+ if (strcmp(csa->field, "min") != 0)
+ error(csa, "wrong problem designator; 'min' expected");
+ read_field(csa);
+ if (!(str2int(csa->field, &nv) == 0 && nv >= 0))
+ error(csa, "number of nodes missing or invalid");
+ read_field(csa);
+ if (!(str2int(csa->field, &na) == 0 && na >= 0))
+ error(csa, "number of arcs missing or invalid");
+ xprintf("Flow network has %d node%s and %d arc%s\n",
+ nv, nv == 1 ? "" : "s", na, na == 1 ? "" : "s");
+ if (nv > 0) glp_add_vertices(G, nv);
+ end_of_line(csa);
+ /* read node descriptor lines */
+ flag = xcalloc(1+nv, sizeof(char));
+ memset(&flag[1], 0, nv * sizeof(char));
+ if (v_rhs >= 0)
+ { rhs = 0.0;
+ for (i = 1; i <= nv; i++)
+ { v = G->v[i];
+ memcpy((char *)v->data + v_rhs, &rhs, sizeof(double));
+ }
+ }
+ for (;;)
+ { read_designator(csa);
+ if (strcmp(csa->field, "n") != 0) break;
+ read_field(csa);
+ if (str2int(csa->field, &i) != 0)
+ error(csa, "node number missing or invalid");
+ if (!(1 <= i && i <= nv))
+ error(csa, "node number %d out of range", i);
+ if (flag[i])
+ error(csa, "duplicate descriptor of node %d", i);
+ read_field(csa);
+ if (str2num(csa->field, &rhs) != 0)
+ error(csa, "node supply/demand missing or invalid");
+ check_int(csa, rhs);
+ if (v_rhs >= 0)
+ { v = G->v[i];
+ memcpy((char *)v->data + v_rhs, &rhs, sizeof(double));
+ }
+ flag[i] = 1;
+ end_of_line(csa);
+ }
+ xfree(flag), flag = NULL;
+ /* read arc descriptor lines */
+ for (k = 1; k <= na; k++)
+ { if (k > 1) read_designator(csa);
+ if (strcmp(csa->field, "a") != 0)
+ error(csa, "wrong line designator; 'a' expected");
+ read_field(csa);
+ if (str2int(csa->field, &i) != 0)
+ error(csa, "starting node number missing or invalid");
+ if (!(1 <= i && i <= nv))
+ error(csa, "starting node number %d out of range", i);
+ read_field(csa);
+ if (str2int(csa->field, &j) != 0)
+ error(csa, "ending node number missing or invalid");
+ if (!(1 <= j && j <= nv))
+ error(csa, "ending node number %d out of range", j);
+ read_field(csa);
+ if (!(str2num(csa->field, &low) == 0 && low >= 0.0))
+ error(csa, "lower bound of arc flow missing or invalid");
+ check_int(csa, low);
+ read_field(csa);
+ if (!(str2num(csa->field, &cap) == 0 && cap >= low))
+ error(csa, "upper bound of arc flow missing or invalid");
+ check_int(csa, cap);
+ read_field(csa);
+ if (str2num(csa->field, &cost) != 0)
+ error(csa, "per-unit cost of arc flow missing or invalid");
+ check_int(csa, cost);
+ a = glp_add_arc(G, i, j);
+ if (a_low >= 0)
+ memcpy((char *)a->data + a_low, &low, sizeof(double));
+ if (a_cap >= 0)
+ memcpy((char *)a->data + a_cap, &cap, sizeof(double));
+ if (a_cost >= 0)
+ memcpy((char *)a->data + a_cost, &cost, sizeof(double));
+ end_of_line(csa);
+ }
+ xprintf("%d lines were read\n", csa->count);
+done: if (ret) glp_erase_graph(G, G->v_size, G->a_size);
+ if (csa->fp != NULL) glp_close(csa->fp);
+ if (flag != NULL) xfree(flag);
+ return ret;
+}
+
+/* eof */
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