#### second question: operator

1/ write a function, calculate and return the product of two numbers; 2/Write a piece of code to call this function and display its result

```
def ji(a,b):
return a*b
ji(2,6)
```

#### third question: standard type operator. Write a script, enter a test score, and output his score (A-F) according to the following criteria.

A:90~100 B:80-89 C:70-79 D:60-69 E:<60

```
def fenshu(a):
if a<60:
return 'F'
elif 60<=a<69:
return 'D'
elif 70<=a<79:
return 'C'
elif 80<=a<89:
return 'B'
else:
return 'A'
fenshu(75)
```

#### 四题 Residual. Determine if a given year is a leap year.

```
def runnian(a):
If (a % 4==0 and a % 100!=0) or (a % 400==0):
Return '闰年'
Else:
Return 'non-leap year'
Def runnian(a):
If (a % 4==0 and a % 100!=0) or (a % 400==0):
Return ('%d is two years' % a)
Else:
Return ('%d is not a leap year' % a)
##Interactive programming
Year = int(input('Please enter the year:'))
If (year % 4==0 and year % 100!=0) or (year % 400==0) :
Print ('%d is leap year ' % year)
Else :
Print ('%d is not a leap year ' % year)
Please enter the year: 1992
1992 is the year
```

- here using input instead of raw-input, because in python3 raw-input is replaced by input. If raw-input appears, the ‘name ‘raw_input’ is not defined’ error will appear.

#### 五题 Residual Take any amount less than $1, then calculate how many coins can be replaced. The coin has 1 cent, 5 cents, 10 cents, and 25 cents.

```
dollar = int(input('Please enter the number of dollars: '))
Cent = dollar*100
a = cent/25
Cent = cent%25
If cent>0:
b = cent/10
Cent = cent%10
If cent>0:
c = cent/5
Cent = cent%5
If cent>0:
d = cent
#First determine whether the variable exists, and then output, avoiding NameError
If 'a' in locals():
Print('\n%d25 cents') % a
If 'b' in locals():
Print('\n%d10 cents') % b
If 'c' in locals():
Print('\n%d5 cents') % c
If 'd' in locals():
Print('\n%d1 cents') % d
```