h,w,sy,sx,n = list(map(int,input().split()))
xy = [[sy,sx,0]] + [list(map(int,input().split())) for i in range(n)]
dp = [0 for i in range(n+1)]

for i in range(1,n+1):
    y,x,c = xy[i-1]
    yy,xx,cc = xy[i]
    
    dp[i] = max(dp[i-2]+cc,dp[i-1])
    
    if y == yy or x == xx or y+x == yy+xx or y-x == yy-xx:
        dp[i] = max(dp[i],dp[i-1]+cc)

print(dp[n])