r - Add dummy variables to data.frame using for-loop -

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i want add 100 dummies t1, t2, ..., t100 data frame df.

df$'t1' <- ifelse(df$x==1, 1, 0) df$'t2' <- ifelse(df$x==2, 1, 0) ... df$'t100' <- ifelse(df$x==100, 1, 0)

using for-loop, tried code this: 

for (i in 1:100) df$paste("t","i",sep="") <- ifelse(df$x == i, 1, 0)

can please correct r code?

for (i in 1:100){      df[[paste("t",i,sep="")]] <- ifelse(df$x == i, 1, 0)  }

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