index error

[surim]

I don't know why these codes makes error message.
Please help me

def dynamic_sort(C):
    C.sort(key = lambda x: x[1])  
    n = len(C)                   
    cache = []               
   
    for y in range(0, n):         
        cache.append(C[y][2])    
    
    return cache

def dynamic_job(C):
    cache = dynamic_sort(C)    
    n = len(C)                   
    for i in range(1, n+1):       
        for k in range(0, i):     
            if C[k][1] <= C[i][0]:         #this line makes the error message(IndexError: list index out of range)
                if cache[k] + C[i][2] > cache[i]:
                    cache[i] = cache[k] + C[i][2] 

    max = 0                      
    for i in range (0, n+1):     
        if max < cache[i]:        
            max = cache[i]       
    return max                    

    



C = [[2,5,6], [4,6,5], [6,7,4], [1,3,5], [5,8,11], [7,9,2]] 

print(dynamic_job(C))

buran write Dec-05-2020, 10:01 AM:
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