How do I create a loop if I have multiple inputs?

Question

I have some inputs

 #Input
 C<-0.05  ## Coupon rate
 y <-0.07   ## Yield to maturity
 m <-5     ## Maturity

And I wish to calculate

rep= c(rep(0,m-1),1)
rep<- rep+C

df<-data.frame(T = 1:m)   
df$CF <- rep
df<- data.frame(df)

df$DF <- 1/(1+y)^(df$T)
df$DC <- df$DF*df$CF

P0 <- sum(df$DC) # initial bond price

df$TDC <-df$T*df$DC # time * discounted CF

STDC <- sum(df$TDC)

The final output I wish to get is this

D_mac_dk1 <- STDC/P0

How can I create a loop if I wish to run a few inputs at once? For example, if I have multiple c,y and m. Thank you.