78 lines
2.4 KiB
Python
78 lines
2.4 KiB
Python
#For loops iterate over a given sequence. Here is an example:
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primes = [2, 3, 5, 7]
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for prime in primes:
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print(prime)
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# Prints out the numbers 0,1,2,3,4
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for x in range(5):
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print(x)
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# Prints out 3,4,5
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for x in range(3, 6):
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print(x)
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# Prints out 3,5,7
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for x in range(3, 8, 2):
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print(x)
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#While loops repeat as long as a certain boolean condition is met. For example:
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# Prints out 0,1,2,3,4
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count = 0
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while count < 5:
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print(count)
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count += 1 # This is the same as count = count + 1
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#break is used to exit a for loop or a while loop, whereas continue is used to skip the current block, and return to the "for" or "while" statement. A few examples:
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# Prints out 0,1,2,3,4
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count = 0
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while True:
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print(count)
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count += 1
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if count >= 5:
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break
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# Prints out only odd numbers - 1,3,5,7,9
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for x in range(10):
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# Check if x is even
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if x % 2 == 0:
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continue
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print(x)
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#Unlike languages like C,CPP.. we can use else for loops. When the loop condition of "for" or "while" statement fails then code part in "else" is executed. If a break statement is executed inside the for loop then the "else" part is skipped. Note that the "else" part is executed even if there is a continue statement.
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# Prints out 0,1,2,3,4 and then it prints "count value reached 5"
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count=0
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while(count<5):
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print(count)
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count +=1
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else:
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print("count value reached %d" %(count))
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# Prints out 1,2,3,4
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for i in range(1, 10):
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if(i%5==0):
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break
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print(i)
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else:
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print("this is not printed because for loop is terminated because of break but not due to fail in condition")
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# Exercise
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# Loop through and print out all even numbers from the numbers list in the same order they are received. Don't print any numbers that come after 237 in the sequence.
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numbers = [
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951, 402, 984, 651, 360, 69, 408, 319, 601, 485, 980, 507, 725, 547, 544,
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615, 83, 165, 141, 501, 263, 617, 865, 575, 219, 390, 984, 592, 236, 105, 942, 941,
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386, 462, 47, 418, 907, 344, 236, 375, 823, 566, 597, 978, 328, 615, 953, 345,
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399, 162, 758, 219, 918, 237, 412, 566, 826, 248, 866, 950, 626, 949, 687, 217,
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815, 67, 104, 58, 512, 24, 892, 894, 767, 553, 81, 379, 843, 831, 445, 742, 717,
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958, 609, 842, 451, 688, 753, 854, 685, 93, 857, 440, 380, 126, 721, 328, 753, 470,
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743, 527
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]
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# your code goes here
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for number in numbers:
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if number == 237:
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break
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if number%2 == 0:
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print(number) |