好未来笔试

第一题SQL：

select CAST(count(1) as SIGNED) from Fans t1
inner join Fans t2
on t1.id = t2.fid and t1.fid = t2.id;

第二题：
最小路径和

class Solution {
    public int minPathSum(int[][] grid) {
        int m = grid.length;
        int n = grid[0].length;
        int[][] dp = new int[m][n];
        dp[0][0] = grid[0][0];
        for(int i = 1;i<m;i++){
            dp[i][0] = dp[i-1][0] + grid[i][0];
        }
        for(int i = 1;i<n;i++){
            dp[0][i] = dp[0][i-1] + grid[0][i];
        }
        for(int i = 1;i<m;i++){
            for(int j = 1;j<n;j++){
                dp[i][j] = Math.min(dp[i-1][j],dp[i][j-1]) + grid[i][j];
            }
        }
        return dp[m-1][n-1];
   }
}