PYTHON

Sum of all substrings of a number

Dp solution:
def sumSubstrings(self,s):
        n = len(s)
        dp = [0] * (n)
        dp[0] = int(s[0])
        res = int(s[0])
        for i in range(1, n):
            dp[i] = (i+1) * int(s[i]) + 10 * (dp[i-1])
            res += dp[i]
        return res % (10**9+7)

Sum of all substrings of a number

//User function Template for Java

class Solution
{
    //Function to find sum of all possible substrings of the given string.
    public static long sumSubstrings(String s)
    {
    long sum=0;
    long mod=1000000007;
    int count=s.length();
    long one=1;
    while(count>0)
    {
       long number=((s.charAt(count-1)-'0')*count)%mod;
       long temp=(one*number)%mod;
       //System.out.println(temp);
       sum=(sum+temp)%mod;
       one=(one*10+1)%mod;
       count--;
    }
    return sum;
    
    }
}
    /*1111*count*number 
 

    222*2
    
  
    33*3
    


     4*count*/