for-loop

问题 I keep getting an error, if without else . I tried else if as well for (;;){ System.out.println("---> Your choice: "); choice = input.nextInt(); if (choice==1) playGame(); if (choice==2) loadGame(); if (choice==3) options(); if (choice==4) credits(); if (choice==5) System.out.println("End of Game\n Thank you for playing with us!"); break; else System.out.println("Not a valid choice!\n Please try again...\n");=[;'mm } also if you have a better idea on how to present this code please do not

问题 I'm just starting to work with lists in java. I'm wondering what the recommended method to modify each element of a list would be? I've been able to get it done with both the following methods, but they both seem fairly unelegant. Is there any better way to get this done in java? And is any of the below methods recommended over the other, or are both on the same level? //Modifying with foreach for (String each : list) { list.set(list.indexOf(each), each+ " blah"); } //Modifying with for for

问题 I'm just starting to work with lists in java. I'm wondering what the recommended method to modify each element of a list would be? I've been able to get it done with both the following methods, but they both seem fairly unelegant. Is there any better way to get this done in java? And is any of the below methods recommended over the other, or are both on the same level? //Modifying with foreach for (String each : list) { list.set(list.indexOf(each), each+ " blah"); } //Modifying with for for

问题 Im trying to make a random number counter game that uses a for loop to print out 6 random numbers 1 - 6. I want to make it so the code can say how many times the number 6 shows in the loop. At the moment I have the code it prints out for a loop of 6 random numbers but it only counts the numbers printed out. For example Welcome to the Dice Game! How many sixes will you roll? 4 2 4 6 4 6 You rolled 2 six(es)! <?php echo"<h1>Welcome to the guess game thing guess how many 6s!</h1>"; $counter = 0;

问题 I am on Python 3.6.7. I just noticed that a for loop over an empty list does not loop even once. After some thought, that made some sense to me. I.e. a loop over a zero-sized (empty) object returns zero iterations. iterable = [] for element in iterable: pass print(element) >>> NameError: name 'element' is not defined This means that a test inside the loop will not be executed if len(iterable) == 0 . iterable = [] for element in iterable: assert isinstance(element, int) #nothing happens Then

问题 I want make some simple loop like this: package main import "fmt" func main() { var i uint32 // code bellow works fine with int32 for i = 31; i >= 0; i-- { fmt.Println(i) } } But this loop is endless, if i has type uint32 . If i is int32 it`s ok. How I can break this loop, if i has type uint32 without checking if i == 0 ? 回答1: i is of type uint32 , so once it reaches 0 , decrementing again will result in the max value of uint32 . Change the loop condition to check for that: var i uint32 //

问题 I want make some simple loop like this: package main import "fmt" func main() { var i uint32 // code bellow works fine with int32 for i = 31; i >= 0; i-- { fmt.Println(i) } } But this loop is endless, if i has type uint32 . If i is int32 it`s ok. How I can break this loop, if i has type uint32 without checking if i == 0 ? 回答1: i is of type uint32 , so once it reaches 0 , decrementing again will result in the max value of uint32 . Change the loop condition to check for that: var i uint32 //

问题 What I have known so far is, multiple declarations inside a block produce an error message and also uninitialized local variable gives garbage value on printing. But coming across an example of for loop in C has shaken my concept on the scope of variables. Below is the code for the same: #include<stdio.h> int main() { int i; for(int i = 5; i > 0 ; i--){ int i; printf("%d ", i); } } The above code produces the output 0 0 0 0 0 I have two questions A for loop is considered as one block then how

问题 I want to calculate the mean NDVI per region (admin level 3, also called woreda), month and year. So my end result would look something like this: regions year month NDVI --------------------------------- region_1 2010 1 0.5 region_1 2010 2 -0.6 region_1 2010 3 0.7 region_1 2010 4 -0.3 region_1 2010 5 0.4 region_1 2010 6 -0.5 region_1 2010 7 0.5 region_1 2010 8 -0.7 region_1 2010 9 0.8 region_1 2010 10 -0.55 region_1 2010 11 -0.3 region_1 2010 12 -0.2 region_2 2010 1 0.5 region_2 2010 2 -0.6

问题 I want to calculate the mean NDVI per region (admin level 3, also called woreda), month and year. So my end result would look something like this: regions year month NDVI --------------------------------- region_1 2010 1 0.5 region_1 2010 2 -0.6 region_1 2010 3 0.7 region_1 2010 4 -0.3 region_1 2010 5 0.4 region_1 2010 6 -0.5 region_1 2010 7 0.5 region_1 2010 8 -0.7 region_1 2010 9 0.8 region_1 2010 10 -0.55 region_1 2010 11 -0.3 region_1 2010 12 -0.2 region_2 2010 1 0.5 region_2 2010 2 -0.6