# include & lt; stdio.h> 
Int main () 
{
Char ch, c, s [2]; \ 
Int m, n, l, I, a; 
Float x, y, z; 
Printf (" Enter the operation of your choice: "); 
Printf (" \ na. Add s.s ubtract \ n "); 
Printf (" m. multiply d.d ivide \ n "); 
Printf (" q.q uit \ n "); 
Scanf_s (" % s ", & amp; S, 2); 
Ch=s [0]; 
The rewind (stdin); 
While (ch! ) 
='q'{
The switch (ch) 
{
Case 'a' : 
{printf (" Enter the first number: \ n "); 
While (scanf_s (" % f ", & amp; X)! 
=1){
Char c=0; 
While (c=getchar ()! ) 
='\ n'Putchar (c); 
Printf (" is not a number, the correct number to the as - 1, 3 or 25, both please enter again "); 
} 
For (I=10, m=0, l=1; L!!!=0; I *=10) 
{
A=(int) (x * I); 
L=a % 10; 
If (l!=0) 
m++; 

} 
Printf (" Enter the second number: \ n "); 
While (scanf_s (" % f ", & amp; Y)! 
=1){
C=0; 
While (c=getchar ()! ) 
='\ n'Putchar (c); 
Printf (" is not a number, the correct number to the as - 1, 3 or 25, both please enter again "); 
} 
For (I=10, n=0, l=1; L!!!=0; I *=10) 
{
A=(int) (x * I); 
L=a % 10; 
If (l!=0) 
n++; 

} 
Z=x + y; 
If (m==0 & amp; & N==0) 
Printf (" %. * f + %. * f=%. * f \ n ", m, x, m, y, m, z); 
The else 
{
If (m & gt; N) 

Printf (" %. * f + %. * f=%. * f \ n ", m, x, m, y, m, z); 
The else 
Printf (" %. * f + %. * f=%. * f \ n ", n, x, n, y, n, z); 
} 


break; 
} 
In case the 's' : 
{printf (" Enter the first number: \ n "); 
While (scanf_s (" % f ", & amp; X)! 
=1){
Char c=0; 
While (c=getchar ()! ) 
='\ n'Putchar (c); 
Printf (" is not a number, the correct number to the as - 1, 3 or 25, both please enter again "); 
} 
For (I=10, m=0, l=1; L!!!=0; I *=10) 
{
A=(int) (x * I); 
L=a % 10; 
If (l!=0) 
m++; 

} 
Printf (" Enter the second number: \ n "); 
While (scanf_s (" % f ", & amp; Y)! 
=1){
Char c=0; 
While (c=getchar ()! ) 
='\ n'Putchar (c); 
Printf (" is not a number, the correct number to the as - 1, 3 or 25, both please enter again "); 
} 
For (I=10, n=0, l=1; L!!!=0; I *=10) 
{
A=(int) (x * I); 
L=a % 10; 
If (l!=0) 
n++; 

} 
Z=x - y; 
If (m==0 & amp; & N==0) 
Printf (" %. * f - %. * f=%. * f \ n ", 0, x, 0, y, 0, z); 
The else 
{
If (m & gt; N) 

Printf (" %. * f - %. * f=%. * f \ n ", m, x, m, y, m, z); 
The else 
Printf (" %. * f - %. * f=%. * f \ n ", n, x, n, y, n, z); 
} 

break; 
} 
Case 'm: 
{printf (" Enter the first number: \ n "); 
While (scanf_s (" % f ", & amp; X)! 
=1){
Char c=0; 
While (c=getchar ()! ) 
='\ n'Putchar (c); 
Printf (" is not a number, the correct number to the as - 1, 3 or 25, both please enter again "); 
} 
For (I=10, m=0, l=1; L!!!=0; I *=10) 
{
A=(int) (x * I); 
L=a % 10; 
If (l!=0) 
m++; 

} 
Printf (" Enter the second number: \ n "); 
While (scanf_s (" % f ", & amp; Y)! 
=1){
Char c=0; 
While (c=getchar ()! ) 
='\ n'Putchar (c); 
Printf (" is not a number, the correct number to the as - 1, 3 or 25, both please enter again "); 
} 
For (I=10, n=0, l=1; L!!!=0; I *=10) 
{
A=(int) (x * I); 
L=a % 10; 
If (l!=0) 
n++; 

} 
Z=x * y; 
If (m==0 & amp; & N==0) 
Printf (" % %. * f *. * f=%. * f \ n ", 0, x, 0, y, 0, z); 
The else 
{
If (m & gt; N) 

Printf (" % %. * f *. * f=%. * f \ n ", m, x, m, y, m, z); 
The else 
Printf (" % %. * f *. * f=%. * f \ n ", n, x, n, y, n, z); 
} 

break; 
} 
Case 'd' : 
{printf (" Enter the first number: \ n "); 
While (scanf_s (" % f ", & amp; X)! 
=1){
Char c=0; 
While (c=getchar ()! ) 
='\ n'Putchar (c); 
Printf (" is not a number, the correct number to the as - 1, 3 or 25, both please enter again \ n "); 
} 
For (I=10, m=0, l=1; L!!!=0; I *=10) 
{
A=(int) (x * I); 
L=a % 10; 
If (l!=0) 
m++; 

} 
Printf (" Enter the second number: \ n "); 
While (scanf_s (" % f ", & amp; Y)!=1 & amp; & ! ((y & gt; 0.0000001) & amp; & (y & lt; 0.0000001))) 
{
Char c=0; 
While (c=getchar ()! ) 
='\ n'Putchar (c); 
Printf (" is not a number, the correct number to the as - 1, 3 or 25, both please enter again \ n "); 
If ((y & gt; 0.0000001) & amp; & (y & lt; 0.0000001)) 
{
Printf (" the divisor can not be 0. Both please enter again \ n "); 
continue; 
} 
} 
For (I=10, n=0, l=1; L!!!=0; I *=10) 
{
A=(int) (x * I); 
L=a % 10; 
If (l!=0) 
n++; 
} 
Z=x/y; 
If (m==0 & amp; & N==0) 
Printf (" %. * f/%. * f=%. * f \ n ", 0, x, 0, y, 0, z); 
The else 
{
If (m & gt; N) 

Printf (" %. * f/%. * f=%. * f \ n ", m, x, m, y, m, z); 
The else 
Printf (" %. * f/%. * f=%. * f \ n ", n, x, n, y, n, z); 
} 

break; 
} 

Case 'q' : break; 
Default: 
{
Printf (" Enter the operation of your choice: "); 
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