Merge pull request #2426 from fwesselm/rawLoops1

Simplify some for loops (part 1)

Author: galabovaa

highs/io/FilereaderEms.cpp

@@ -269,12 +269,10 @@ HighsStatus FilereaderEms::writeModelToFile(const HighsOptions& options,
     f << "names" << std::endl;
 
     f << "columns" << std::endl;
-    for (size_t i = 0; i < lp.col_names_.size(); i++)
-      f << lp.col_names_[i] << std::endl;
+    for (const auto& name : lp.col_names_) f << name << std::endl;
 
     f << "rows" << std::endl;
-    for (size_t i = 0; i < lp.row_names_.size(); i++)
-      f << lp.row_names_[i] << std::endl;
+    for (const auto& name : lp.row_names_) f << name << std::endl;
   }
 
   // todo: integer variables.

highs/io/FilereaderLp.cpp

@@ -70,8 +70,7 @@ FilereaderRetcode FilereaderLp::readModelFromFile(const HighsOptions& options,
     //
     lp.offset_ = m.objective->offset;
     lp.col_cost_.resize(lp.num_col_, 0.0);
-    for (size_t i = 0; i < m.objective->linterms.size(); i++) {
-      std::shared_ptr<LinTerm> lt = m.objective->linterms[i];
+    for (const auto& lt : m.objective->linterms) {
       lp.col_cost_[varindex[lt->var->name]] = lt->coef;
     }
 
@@ -177,8 +176,7 @@ FilereaderRetcode FilereaderLp::readModelFromFile(const HighsOptions& options,
     // column 0, so have to clear this before pushing back start
     lp.a_matrix_.start_.clear();
     assert((int)lp.a_matrix_.start_.size() == 0);
-    for (HighsInt i = 0; i < lp.num_col_; i++) {
-      std::shared_ptr<Variable> var = m.variables[i];
+    for (const auto& var : m.variables) {
       lp.a_matrix_.start_.push_back(nz);
       for (size_t j = 0; j < consofvarmap_index[var].size(); j++) {
         double value = consofvarmap_value[var][j];

highs/io/HMpsFF.cpp

@@ -108,8 +108,8 @@ FreeFormatParserReturnCode HMpsFF::loadProblem(
 
   // Only set up lp.integrality_ if non-continuous
   bool is_mip = false;
-  for (size_t iCol = 0; iCol < col_integrality.size(); iCol++) {
-    if (col_integrality[iCol] != HighsVarType::kContinuous) {
+  for (const auto& var_type : col_integrality) {
+    if (var_type != HighsVarType::kContinuous) {
       is_mip = true;
       break;
     }

highs/lp_data/HighsIis.cpp

@@ -204,10 +204,8 @@ HighsStatus HighsIis::getData(const HighsLp& lp, const HighsOptions& options,
   if (this->compute(to_lp, options) != HighsStatus::kOk)
     return HighsStatus::kError;
   // Indirect the values into the original LP
-  for (HighsInt iCol = 0; iCol < HighsInt(this->col_index_.size()); iCol++)
-    this->col_index_[iCol] = from_col[this->col_index_[iCol]];
-  for (HighsInt iRow = 0; iRow < HighsInt(this->row_index_.size()); iRow++)
-    this->row_index_[iRow] = from_row[this->row_index_[iRow]];
+  for (HighsInt& colindex : this->col_index_) colindex = from_col[colindex];
+  for (HighsInt& rowindex : this->row_index_) rowindex = from_row[rowindex];
   if (kIisDevReport) this->report("On exit", lp);
   return HighsStatus::kOk;
 }

highs/lp_data/HighsInfo.h

@@ -169,7 +169,7 @@ class HighsInfo : public HighsInfoStruct {
 
  private:
   void deleteRecords() {
-    for (size_t i = 0; i < records.size(); i++) delete records[i];
+    for (auto record : records) delete record;
   }
 
   void initRecords() {

highs/lp_data/HighsInterface.cpp

@@ -308,8 +308,7 @@ HighsStatus Highs::formStandardFormLp() {
     }
   }
   // Now add the slack variables
-  for (HighsInt iX = 0; iX < HighsInt(slack_ix.size()); iX++) {
-    HighsInt iRow = slack_ix[iX];
+  for (HighsInt iRow : slack_ix) {
     this->standard_form_cost_.push_back(0);
     if (iRow > 0) {
       this->standard_form_matrix_.index_.push_back(iRow - 1);
@@ -3312,11 +3311,11 @@ HighsStatus Highs::computeIllConditioning(
                      ss.str().c_str());
     }
   } else {
-    for (HighsInt iX = 0; iX < HighsInt(ill_conditioning.record.size()); iX++) {
+    for (const auto& rec : ill_conditioning.record) {
       ss.str(std::string());
       bool newline = false;
-      double multiplier = ill_conditioning.record[iX].multiplier;
-      HighsInt iCol = basic_var[ill_conditioning.record[iX].index];
+      double multiplier = rec.multiplier;
+      HighsInt iCol = basic_var[rec.index];
       if (iCol < incumbent_lp.num_col_) {
         std::string col_name = has_col_names ? incumbent_lp.col_names_[iCol]
                                              : "C" + std::to_string(iCol);

highs/lp_data/HighsLpUtils.cpp

@@ -788,9 +788,9 @@ bool costScaleOk(const vector<double>& cost, const HighsInt cost_scale,
                  const double infinite_cost) {
   if (!cost_scale) return true;
   double cost_scale_value = std::pow(2, cost_scale);
-  for (HighsInt iCol = 0; iCol < HighsInt(cost.size()); iCol++)
-    if (std::abs(cost[iCol]) < kHighsInf &&
-        std::abs(cost[iCol] * cost_scale_value) > infinite_cost)
+  for (double c : cost)
+    if (std::abs(c) < kHighsInf &&
+        std::abs(c * cost_scale_value) > infinite_cost)
       return false;
   return true;
 }

highs/lp_data/HighsOptions.h

@@ -1553,7 +1553,7 @@ class HighsOptions : public HighsOptionsStruct {
   }
 
   void deleteRecords() {
-    for (size_t i = 0; i < records.size(); i++) delete records[i];
+    for (auto record : records) delete record;
   }
 
  public:

highs/lp_data/HighsSolution.cpp

@@ -1772,8 +1772,8 @@ void reportLpKktFailures(const HighsLp& lp, const HighsOptions& options,
 }
 
 bool HighsSolution::hasUndefined() const {
-  for (HighsInt iCol = 0; iCol < HighsInt(this->col_value.size()); iCol++)
-    if (this->col_value[iCol] == kHighsUndefined) return true;
+  for (double value : this->col_value)
+    if (value == kHighsUndefined) return true;
   return false;
 }
 

highs/mip/HighsDomain.cpp

@@ -2924,8 +2924,7 @@ bool HighsDomain::ConflictSet::resolveLinearGeq(HighsCDouble M, double Mupper,
   resolvedDomainChanges.clear();
   double covered = double(M - Mupper);
   if (covered > 0) {
-    for (HighsInt k = 0; k < (HighsInt)resolveBuffer.size(); ++k) {
-      ResolveCandidate& reasonDomchg = resolveBuffer[k];
+    for (const auto& reasonDomchg : resolveBuffer) {
       LocalDomChg locdomchg;
       locdomchg.pos = reasonDomchg.boundPos;
       locdomchg.domchg = localdom.domchgstack_[reasonDomchg.boundPos];
@@ -3034,8 +3033,7 @@ bool HighsDomain::ConflictSet::resolveLinearLeq(HighsCDouble M, double Mlower,
   resolvedDomainChanges.clear();
   double covered = double(M - Mlower);
   if (covered < 0) {
-    for (HighsInt k = 0; k < (HighsInt)resolveBuffer.size(); ++k) {
-      ResolveCandidate& reasonDomchg = resolveBuffer[k];
+    for (const auto& reasonDomchg : resolveBuffer) {
       LocalDomChg locdomchg;
       locdomchg.pos = reasonDomchg.boundPos;
       locdomchg.domchg = localdom.domchgstack_[reasonDomchg.boundPos];