Compare these two versions.
g=integer(5)
for (i in g){
print(paste("i = ", i))
g[i]=g[i]+1
}
[1] "i = 0"
[1] "i = 0"
[1] "i = 0"
[1] "i = 0"
[1] "i = 0"
g=integer(5)
for (i in seq_along(g)){
print(paste("i = ", i))
g[i]=g[i]+1
}
[1] "i = 1"
[1] "i = 2"
[1] "i = 3"
[1] "i = 4"
[1] "i = 5"
g
[1] 1 1 1 1 1