#Problem:
#T - time vector
#V - value vector
#for each monotone(sp?) time segment
#and each i find j <= i
#such that T[i]-T[j] less or equal a given time interval

t = c(1,2,4,5,6,8,13,14,16,19,20,21,1,2,4,5,6,8)
v = c(-1.0, 1.2, 1.0, 0.4, 0.3, 1.7, 0.9, -0.9, 1.5, -0.4, 1.6, 3.8,-1.0, 1.2, 1.0, 0.4, 0.3, 1.7)
r = rep(0, length(t))
s = rep(0, length(t))

r[1] = 1
s[1] = v[1]
j = 1
timeInt = 5
for (i in 2:length(t)){
  if (t[i] < t[i-1]){
    r[i] = i
    s[i] = v[i]
    j = i
  }else{
    s[i] = s[i-1]
    while (t[i] - t[j] > timeInt) {
      s[i] = s[i] - v[j]
      j = j+1
    }
  r[i] = j
  s[i] = s[i] + v[i]
  }
}

#v = rnorm(1000000)
#m = matrix(rnorm(1000000))
#f5 = function(v){for (i in 1:length(v)) b = v[i]}
#system.time(o<-f5(v),gcFirst=TRUE)
#system.time(o<-f5(m),gcFirst=TRUE)