title: Ways Transforming One String Removing 0 Characters
signature: function waysTransformingOneStringRemoving0Characters($a, $b) {
source_py: def ways_transforming_one_string_removing_0_characters(a, b):
      n = len(a)
      m = len(b)
      if (m == 0):
          return 1
      dp = [([0] * (n + 1)) for _ in range((m + 1))]
      for i in range(m):
          for j in range(i, n):
              if (i == 0):
                  if (j == 0):
                      if (a[j] == b[i]):
                          dp[i][j] = 1
                      else:
                          dp[i][j] = 0
                  elif (a[j] == b[i]):
                      dp[i][j] = (dp[i][(j - 1)] + 1)
                  else:
                      dp[i][j] = dp[i][(j - 1)]
              elif (a[j] == b[i]):
                  dp[i][j] = (dp[i][(j - 1)] + dp[(i - 1)][(j - 1)])
              else:
                  dp[i][j] = dp[i][(j - 1)]
      return dp[(m - 1)][(n - 1)]
source_cpp: int ways_transforming_one_string_removing_0_characters(string a, string b) {
    int n = a . size ( ), m = b . size ( );
    if ( m == 0 ) return 1;
    int dp [ m + 1 ] [ n + 1 ];
    memset ( dp, 0, sizeof ( dp ) );
    for ( int i = 0;
    i < m;
    i ++ ) {
      for ( int j = i;
      j < n;
      j ++ ) {
        if ( i == 0 ) {
          if ( j == 0 ) dp [ i ] [ j ] = ( a [ j ] == b [ i ] ) ? 1 : 0;
          else if ( a [ j ] == b [ i ] ) dp [ i ] [ j ] = dp [ i ] [ j - 1 ] + 1;
          else dp [ i ] [ j ] = dp [ i ] [ j - 1 ];
        }
        else {
          if ( a [ j ] == b [ i ] ) dp [ i ] [ j ] = dp [ i ] [ j - 1 ] + dp [ i - 1 ] [ j - 1 ];
          else dp [ i ] [ j ] = dp [ i ] [ j - 1 ];
        }
      }
    }
    return dp [ m - 1 ] [ n - 1 ];
  }