Why the counts value fail to aggregate?-CodePudding

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I was expecting the returned counts to be 5 as in 5 'a's in the nested loops, but it returns counts as 1.

CodePudding user response：

You could fix the second loop to:

   for j in range(len(fleet_grid[i])):   # then loop each of item in col.

CodePudding user response：

Try this and it should help you understand what's missing (wrong): (it's very easy to just add a few print here-n-there to see what's happening is what's supposed to)

Also it's helpful to learn how to debug such a small program next time - use visual platform like https://pythontutor.com/

grid = [['a', 'a', 'a'], ['b', 'b', 'b'], ['1', 'a', 'a']]

counts = 0

rows = len(grid)
cols = len(grid[0])

for i in range(rows):
    for j in range(cols):           # if alll columns are the same size
    #for j in range(len(grid[i])):  # if not all col. have the same size
        if grid[i][j]  == 'a':    # 
            print(i,j)
            counts  = 1

print(counts)  # 5

Alternatively, you can do this way: (but not recommend for learning:)

flatted = sum(grid, [])
print(flatted)

counts = sum(1 for x in flatted if x == 'a')    # sum(*generator exp.*)
print(counts)       # 5

CodePudding user response：

Try changing

for j in range(i)

for j in range(len(fleet_grid[i]))

otherwise you're not counting every character.