from sys import stdin

def main():
    inf = float(1e3000)
    
    l = []
    a = l.append
    for s in stdin:
        a(s)
    n = len(l)
    nm = [None] * n
    nd = 0
    for lj in l:
        nm[nd] = [inf] * n
        s = lj.split
        for k in s():
            d = k.split(':')
            nb = int(d[0])
            vt = int(d[1])
            nm[nd][nb] = vt
        nd += 1
    
    c = 0
    sn = [{0:None},[e for e in nm[0]]]
    r = n-1
    
    while r > 0:
        f = [inf, None]
        for i in xrange(n):
            if sn[1][i] < f[0]:
                f = [sn[1][i], i]
        
        c += f[0]
        sn[0][f[1]] = None
        
        for i in xrange(n):
            if i in sn[0]:
                sn[1][i] = inf
            else:
                sn[1][i] = min(sn[1][i], nm[f[1]][i])

        r -= 1
        
    print c
                    
main()