换钱最少货币数

public int mincoinsl(int[] arr, int aim){
    if (arr == null || arr.length == 0 || aim < 0){
       return -1;
   }
    int n = arr.length;
  int max = Integer.MAX_VALUE;
 int[][] dp = new int[n][aim+1];
  for (int j = 1; j < aim +1; j ++){
        dp[0][j]  = max;
     if (j - arr[0] >= 0 && dp[0][j-arr[0]] != max){
           dp[0][j] = dp[0][j-arr[0]] + 1;
      }
    }
    
 int left = 0;
    for (int i = 1; i < n; i++){
      for (int j = 1; j < aim +1; j++){
         left = max;
          if (j - arr[i] >=0 && dp[i][j-arr[i]] != max)            {
                left = dp[i][j-arr[i]] +1;
           }
            dp[i][j] = Math.min(left,dp[i-1][j]);       
     }
    }
    
 return dp[n-1][aim] != max ? dp[n-1][aim]:-1;
}

public int mincoinsl(int[] arr, int aim){
  if (arr == null || arr.length== 0|| aim <0){
      return -1;
   }
    int n = arr.length;
  max = Integer.MAX_VALUE;
 int[] dp = new int[aim+1];
   
 for (int j = 1; j < aim+1; j++){
      dp[j] = max;
     if (j-arr[0]>=0 && dp[j-arr[0]] !=max){
           dp[j] = dp[j-arr[0]] + 1;
        }
    }
    
 int left = 0;
    for (int i = 1; i < n; i ++){
     for (int j = 1; j < aim+1; j++){
          if (j- arr[i]>=0&& dp[j-arr[i]] !=max)
                left = dp[j-arr[i]] +1;
          dp[j]= Math.min(left,dp[j]);
     }
    }
    return dp[aim] != max ? dp[aim]:-1;
}