Dividing a value and adding it to other rows using dplyr

Question

I wrote this code that does is the following.

In the table mo102 there are costs that I want to divide and add equally to the rows of the table table_reduced that share the same values on some particular columns. Those columns are id_s, t_hab, p_d.

The problem is that using a for loop is not optimal and takes a lot of time. Is there a solution using dplyr to do this?

tblsin = as.data.frame(0, col.names = colnames(table_reduced))
lsin = length(mo102[[1]])
for (i in 1:lsin) {
  ns <- mo102[[3]][i]
  t_hab <- mo102[[4]][i]
  p_d <- mo102[[5]][i]
  cout_s <- mo102[[6]][i]

  temp <- table_reduced %>% filter(., ID_S %in% ns & T_HAB %in% t_hab & P_D %in% p_d & code_b != "MO102") 
  len <- length(temp[[1]])

  if (len != 0) {
    temp <- mutate(temp, total_cost = total_cost + cout_s/len)
    tblsin = bind_rows(tblsin, temp)
  }

}

A mo102 table looks like this:

   piece.agr  DS_ESTETICO_PARTIDA           ID_SINIESTRO TIPO_HAB_D DS_PARTE_D total_cost
3       ASE            Directos 100210#000000986776904#2        ASE    _DIVERS        160

table_reduced looks like this:

              ID_SINIESTRO piece.agr          TIPO_HAB_D          DS_PARTE_D DS_ESTETICO_PARTIDA code_bareme total_cost
                     <chr>     <chr>               <chr>               <chr>               <chr>       <chr>      <dbl>
2 100210#000000331493904#2       COC                 ASE             _DIVERS           Esteticos        P003     264.60

5 100210#000000986776904#2       ASE                 ASE             _DIVERS            Directos       PB101      94.20

The result I want is a table_reduced where the data from total_cost from the table mo102 is divided by two and added to each of the rows, since they have the same attributes.

Since 160 is the cost on mo120, it is divided by 2 (number of identical rows) and added to these rows.

So like this:

              ID_SINIESTRO piece.agr          TIPO_HAB_D          DS_PARTE_D DS_ESTETICO_PARTIDA code_bareme total_cost
                     <chr>     <chr>               <chr>               <chr>               <chr>       <chr>      <dbl>
2 100210#000000331493904#2       COC                 ASE             _DIVERS           Esteticos        P003     344.60

5 100210#000000986776904#2       ASE                 ASE             _DIVERS            Directos       PB101      174.20