import bisect

def main():
    import sys
    input = sys.stdin.read
    data = input().split()
    ptr = 0
    N = int(data[ptr])
    ptr += 1
    M = int(data[ptr])
    ptr += 1
    X = int(data[ptr])
    ptr += 1
    
    C = list(map(int, data[ptr:ptr+N]))
    ptr += N
    
    # Convert C to 1-based index
    C = [0] + C
    
    sumY = dict()
    for _ in range(M):
        A_j = int(data[ptr])
        ptr += 1
        B_j = int(data[ptr])
        ptr += 1
        Y_j = int(data[ptr])
        ptr += 1
        
        key = (A_j, B_j)
        if key not in sumY:
            sumY[key] = 0
        sumY[key] += Y_j
    
    # Preprocess for each B, the list of i's where C_i = B
    from collections import defaultdict
    pos = defaultdict(list)
    for i in range(1, N+1):
        b = C[i]
        pos[b].append(i)
    # Sort the lists for binary search
    for b in pos:
        pos[b].sort()
    
    delta = [0] * (N + 1)
    
    for (A, B), y in sumY.items():
        if B not in pos:
            continue
        lst = pos[B]
        idx = bisect.bisect_left(lst, A)
        for i in lst[idx:]:
            k = i - A
            if 0 <= k <= N:
                delta[k] += y
    
    max_score = 0
    for k in range(0, N+1):
        score = X * k + delta[k]
        if score > max_score:
            max_score = score
    print(max_score)

if __name__ == "__main__":
    main()