why my code get this error error

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Any one can help me? why my code get this error error: expected class-name before ‘(‘ token error: expected ‘{‘ before ”’ token error: expected unqualified-id before ‘)’ token === Build failed: 3 error(s), O warning(s) (0 minute(s), 0 second(s)) === This my code: class Board:public State(){ private: vectorblocks; public: void generateIntlState() { int bIndex = 0; intializeBlocks(); for(int r = 0; r for(int c = 0; c setVal(r,c blocks[bIndex]); bIndex ++; } } pushBlockDown(); } void intializeBlocks(){ int zeroCount = 1; for (int i = 1; i blocks.push_back(i); if(zeroCount<> blocks.push_back(0); } zeroCount++; } for( int i = 8; i > 0; i–){ int num=rand()% i; int temp = blocks[i]; blocks[i] = blocks[num]; blocks[num] = temp; } } void findActHeuristic(priority_queue&actions, Goal g){ Action a; vectoractions_vec; vector states; int h = 0; for(int r = 0; r for(int c = 0; c if((r != c)&&(isFull(r))&&(isEmptu(c))){ a.setAction(r,c); actions_vec.push_back(a); } } } for(int i = 0; i State newState = nextState(actions_vec[i]); states.push_back(newState); if(newState.getVal(g.getRow(),g.getColumn()) == g.getVal()){ h = 100; }else if(newState.isOnTop(g.getVal())&&(newState.isColumnEmpty(g.getColumn()))){ h = 95; }else if(newState.isOnTop(g.getVal())&&(newState.isBlockEmpty(g.getColumn()))){ h = 85; }else if(newState.isBlockEmpty(g.getRow(),g.getColumn())){ h = 65; }else if(newState.isColumnEmpty(g.getColumn()))&&(getRowPos(g.getVal()) > g.getRow()){ h = 55; }else if(newState.isColumnEmpty(g.getColumn())){ h = 50; }else if(newState.isOnTop(ggetVal())){ h = 40; }else if(newState.isColumnFull(g.getColumn())){ h = 1; }else{ h = 5; } actions_vec[i].setHeuristic(h); actions.push(actions_vec[i]); } templatevoid priority_queueQ(priority_queueq){ while(!q.empty()){ q.top().printGoal(); q.pop(); } cout <> } } };

The Correct Answer and Explanation is :

The errors you’re encountering in your C++ code are related to syntax issues, particularly with class declarations and member function definitions. Let’s address each error and provide solutions:

1. Error: expected class-name before ‘(‘ token

This error typically occurs when the compiler expects a class name but encounters something else. In your code, the declaration:

class Board:public State(){

is incorrect. The parentheses after State are unnecessary and syntactically incorrect. The correct syntax for inheritance in C++ is:

class Board : public State {

Ensure that State is a valid class that has been properly declared and included in your project.

2. Error: expected ‘{‘ before ”’ token

This error suggests that the compiler encountered an unexpected character, likely due to a missing or misplaced symbol. In your code, the function definition:

void intializeBlocks(){

has a syntax error. The correct function declaration should be:

void initializeBlocks() {

Additionally, ensure that all function definitions are properly enclosed within curly braces {}.

3. Error: expected unqualified-id before ‘)’ token

This error often arises from incorrect function declarations or missing headers. In your code, the function:

void findActHeuristic(priority_queue&actions, Goal g){

is missing a space between & and actions. The corrected declaration is:

void findActHeuristic(priority_queue& actions, Goal g) {

Ensure that priority_queue and Goal are properly declared and included in your project.

General Recommendations:

  • Include Directives: Verify that all necessary header files are included at the beginning of your source files. For example, if you’re using vector, include:
  #include <vector>
  • Function Definitions: Ensure that all member functions are defined with the correct syntax, including proper use of curly braces {}.
  • Spelling and Case Sensitivity: C++ is case-sensitive. Ensure that all identifiers are spelled correctly and consistently. For instance, intializeBlocks should be initializeBlocks.
  • Class Declarations: When inheriting from a base class, ensure that the base class is properly declared and included. For example:
  #include "State.h" // Ensure this header file exists and is correctly included

By addressing these syntax issues and ensuring proper declarations and inclusions, your code should compile without the mentioned errors.

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