5.3（2）----机器人走方格2（CC150）

public static int countWays(int[][] map,int x, int y){

        if( x < 0 || y < 0) return -1;

        int[][] dp = new int[x][y];
        for(int i = 0; i < x; i++){
            if(map[i][0] == 1){
                dp[i][0] = 1;
            }
            else{
                break;
            }
        }
        for(int j = 0; j < y; j++){
            if(map[0][j] != 1) break;
            dp[0][j] = 1;
        }
        for(int i = 1; i < x; i++){
            for(int j = 1; j < y; j++){
                if(map[i][j] != 1){
                    dp[i][j] = 0;
                }
                else{
                    dp[i][j] = dp[i-1][j] + dp[i][j-1];
                }
            }
        }
        return dp[x-1][y-1];
    }
}