rand.c

// Order and Chaos AI: Random player.  - Tom Smeding

#include "params.h"

#define _XOPEN_SOURCE 700  // random
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <stdint.h>

#include "ai.h"

#ifndef ASSERTS
#define NDEBUG
#endif
#include <assert.h>

#define INF 1000000000 //1e9

#include "winmasks.h"
const uint64_t fullmask=(1ULL<<(N*N))-1;

#define APPLY(bitmap,idx) do {(bitmap)|=1ULL<<(idx);} while(0)
#define REMOVE(bitmap,idx) do {(bitmap)&=~(1ULL<<(idx));} while(0)
#define ISEMPTY(bitmap,idx) (!((bitmap)&(1ULL<<(idx))))

Board* makeboard(void){
	return calloc(1,sizeof(Board));
}

void applymove(Board *board,Move mv){
	APPLY(board->b[mv.stone],mv.pos);
}

bool isempty(const Board *board,int pos){
	return ISEMPTY(board->b[0]|board->b[1],pos);
}

void printboard(const Board *board){
	uint64_t b0=board->b[0],b1=board->b[1];
	for(int y=0;y<N;y++){
		for(int x=0;x<N;x++){
			fputc(".OX"[(b0&1)+2*(b1&1)],stderr);
			fputc(' ',stderr);
			b0>>=1;
			b1>>=1;
		}
		fputc('\n',stderr);
	}
}

int checkwin(const Board *board){
	for(int i=0;i<nwinmasks;i++){
		if((board->b[0]&winmasks[i])==winmasks[i]||
		   (board->b[1]&winmasks[i])==winmasks[i])return ORDER;
	}
	if(((board->b[0]|board->b[1])&fullmask)==fullmask)return CHAOS;
	return -1;
}

Move calcmove(Board *board,int player){
	(void)player;
	Move poss[2*N*N];
	int nposs=0;

	for(int p=0;p<N*N;p++){
		for(int stone=0;stone<2;stone++){
			if(!ISEMPTY(board->b[0]|board->b[1],p))continue;
			poss[nposs].pos=p;
			poss[nposs++].stone=stone;
		}
	}

	if(nposs==0){
		Move mv={-1,-1};
		return mv;
	}
	return poss[random()%nposs];
}