if-statement

问题 hey guys im just learning C# in school and am having trouble figuring out how i can use a variable outside of an if statement when that variable is already declared inside an if statement..heres what my program looks like........i have to use the "factor" variable outside of the if statemants because it is part of an equation that i need for a school assignment..if i am missing anything or you need more information, plz dont hesitate to tell me public caloriesCalculator() {

问题 I am using a trim formula in excel: TRIM(LEFT(SUBSTITUTE(MID(M2,FIND("|",SUBSTITUTE(M2,"-","|",2))+1,LEN(M2)),"-",REPT(" ",LEN(M2))),LEN(M2))) this looks for a number in between a string of 4 numbers: 193449542-27309370502-9045796-169794419204 which works perfectly. I want to add an if= when a another cell on that same row contains either "bing" or "Adwords" and skip cells that contain it. 回答1: In H2 per the supplied image, =IF(NOT(SUM(COUNTIF(J2, "*"&{"bing","Adwords"}&"*"))), TRIM(LEFT

问题 Could someone explain the following behavior of the " if " block of bash ? I use the following simple code check if the first_value is less than the second_value first_value=67 second_value=2 if [[ "${first_value}" < "${second_value}" ]]; then echo "Yes" else echo "No" fi The issue is If the second_value is 1,2,3,4,5,6,10,11,... the block will return "No" But if the second_value is 7,8,9 the block will return "Yes" (must be "No") The fix is to use " -lt " instead of " < " but I want to

问题 I have written a program that checks if a chess board is valid. In one part of my code I test, if the amounts of the pieces are correct. count is dictionary, which is an inventory of the board I want to check. For example (b stands for black, w fo white): count = {'bking': 1, 'wking': 1, 'bpawn': 3, 'bbishop': 1, 'wrook': 1, 'wqueen': 1} the possible colors and pieces are available in lists: colors = ['b', 'w'] pieces = ['queen', 'rook', 'knight', 'bishop', 'pawn'] I have the following ugly

问题 I write something like this in Ruby: if a.max == a[0] brand = b[0] elsif a.max == a[1] brand = b[1] elsif a.max == a[2] brand = b[2] elsif a.max == a[3] brand = b[3] end a and b both are unique arrays. Is there any way to check all if and elsif 's in the same condition? Only one condition for a[0] , a[1] , a[2] and a[3] ? 回答1: Array#index might help in cases like these (assuming the size of a and b is the same): brand = b[a.index(a.max)] In cases in which the array a might be empty, you will

问题 I've seen something along the lines of if ! some-command; then #do something fi What's the effect of the exclamation point? I see that if you use brackets, it can be used for negation. Is that the same effect here? 回答1: As documented in man bash : If the reserved word ! precedes a pipeline, the exit status of that pipeline is the logical negation of the exit status as described above. 回答2: Correct. Here is a code sample: anny ~> if ! grep $USER /etc/passwd More input> then echo "your user

问题 I've seen something along the lines of if ! some-command; then #do something fi What's the effect of the exclamation point? I see that if you use brackets, it can be used for negation. Is that the same effect here? 回答1: As documented in man bash : If the reserved word ! precedes a pipeline, the exit status of that pipeline is the logical negation of the exit status as described above. 回答2: Correct. Here is a code sample: anny ~> if ! grep $USER /etc/passwd More input> then echo "your user

问题 I've seen something along the lines of if ! some-command; then #do something fi What's the effect of the exclamation point? I see that if you use brackets, it can be used for negation. Is that the same effect here? 回答1: As documented in man bash : If the reserved word ! precedes a pipeline, the exit status of that pipeline is the logical negation of the exit status as described above. 回答2: Correct. Here is a code sample: anny ~> if ! grep $USER /etc/passwd More input> then echo "your user

问题 Is there a way to check if a class has been defined/exists? I have different options on a menu, and some of them require inherited variables, so if you try to select that function before you have set the variables, it crashes. My class is called Gen0, and I started it by simply putting class Gen0(): Followed by the rest of the code to set the variables. For context, I am doing a population model, so the initial values need to be set (option 1) before displaying (option 2), using (option 3) or

问题 Is there a way to check if a class has been defined/exists? I have different options on a menu, and some of them require inherited variables, so if you try to select that function before you have set the variables, it crashes. My class is called Gen0, and I started it by simply putting class Gen0(): Followed by the rest of the code to set the variables. For context, I am doing a population model, so the initial values need to be set (option 1) before displaying (option 2), using (option 3) or