1552F - Telepanting - CodeForces Solution

n = int(input())

X, Y, S = [], [], []
P = 998244353

T = [0]*(n+1)


def findIndex(L, p):
    
    
    n = len(L)
    
    l, r = 0, n
    guess = n // 2
    
    while r > l:
        guess = (r+l) // 2
        
        if L[guess] <= p:
            l = guess + 1
            
        elif L[guess] > p:
            r = guess
    
    return l


for i in range(n):
    xi, yi, si = map(int, input().split())
    
    X.append(xi)
    Y.append(yi)
    S.append(si)
    
    j = findIndex(X, yi)
        
    T[i+1] = (xi-yi + 2*T[i] - T[j]) % P

xn = X[-1]
total = xn+1
Test = [0]*n

for i in range(n):
    si = S[i]
    
        
    total += (T[i+1]-T[i]) * si
    total %= P
    

print(total)