## File: polyhedron_minimize.c

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isl 0.20-2
 `123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105` ``````/* * Copyright 2008-2009 Katholieke Universiteit Leuven * * Use of this software is governed by the MIT license * * Written by Sven Verdoolaege, K.U.Leuven, Departement * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium */ #include #include #include #include #include #include /* The input of this program is the same as that of the "polytope_minimize" * program from the barvinok distribution. * * Constraints of set is PolyLib format. * Linear or affine objective function in PolyLib format. */ static struct isl_vec *isl_vec_lin_to_aff(struct isl_vec *vec) { struct isl_vec *aff; if (!vec) return NULL; aff = isl_vec_alloc(vec->ctx, 1 + vec->size); if (!aff) goto error; isl_int_set_si(aff->el[0], 0); isl_seq_cpy(aff->el + 1, vec->el, vec->size); isl_vec_free(vec); return aff; error: isl_vec_free(vec); return NULL; } /* Rotate elements of vector right. * In particular, move the constant term from the end of the * vector to the start of the vector. */ static struct isl_vec *vec_ror(struct isl_vec *vec) { int i; if (!vec) return NULL; for (i = vec->size - 2; i >= 0; --i) isl_int_swap(vec->el[i], vec->el[i + 1]); return vec; } int main(int argc, char **argv) { struct isl_ctx *ctx = isl_ctx_alloc(); struct isl_basic_set *bset; struct isl_vec *obj; struct isl_vec *sol; isl_int opt; unsigned dim; enum isl_lp_result res; isl_printer *p; isl_int_init(opt); bset = isl_basic_set_read_from_file(ctx, stdin); assert(bset); obj = isl_vec_read_from_file(ctx, stdin); assert(obj); dim = isl_basic_set_total_dim(bset); assert(obj->size >= dim && obj->size <= dim + 1); if (obj->size != dim + 1) obj = isl_vec_lin_to_aff(obj); else obj = vec_ror(obj); res = isl_basic_set_solve_ilp(bset, 0, obj->el, &opt, &sol); switch (res) { case isl_lp_error: fprintf(stderr, "error\n"); return -1; case isl_lp_empty: fprintf(stdout, "empty\n"); break; case isl_lp_unbounded: fprintf(stdout, "unbounded\n"); break; case isl_lp_ok: p = isl_printer_to_file(ctx, stdout); p = isl_printer_print_vec(p, sol); p = isl_printer_end_line(p); p = isl_printer_print_isl_int(p, opt); p = isl_printer_end_line(p); isl_printer_free(p); } isl_basic_set_free(bset); isl_vec_free(obj); isl_vec_free(sol); isl_ctx_free(ctx); isl_int_clear(opt); return 0; } ``````