7-4 Expression conversions (25 points)

The arithmetic expression has the form of prefix notation, infix notation and suffix notation. The arithmetic expression used in daily use is infix notation, that is, the two-dollar operator is in the middle of two operands. Please design your program to convert infix expressions to suffix expressions. Input Format:

The input gives an infix expression with no spaces in one line, which can contain + 、-、 *, \, and left and right brackets (), with an expression of no more than 20 characters. output Format:

outputting the converted suffix expression on a single line requires that different objects (operands, operation symbols) be separated by a space, but with no extra space at the end. Input Sample:

2+3* (7-4) +8/4

Sample output:

2 3 7 4-* + 8 4/+
 
code:

#include <stdio.h> #include <string.h> int isnum (char ch);
int Zhengfu (char ch);
int compare (char A,char b);
void F (char *a,int len);
	int main () {char a[25];
	scanf ("%s", a);
	int Len=strlen (a);
	F (A,len);
return 0; } int isnum (char ch) {return ch>= ' 0 ' &&ch<= ' 9 ' | |
ch== '. '; } int Zhengfu (char ch) {return ch== ' + ' | |
ch== '-';
	} int Compare (char A,char b) {//Determine if stack if (b== ') ') return 1; if (a== ' | | |
	b== ' (') return 0; if (b== ' + ' | |
	b== '-') return 1; else if (b== ' * ' | | b== '/') {if (a== ' + ' | |
		a== '-') return 0; else if (a== ' * ' | |
	a== '/') return 1;
	}} void F (char *a,int len) {char stack[25];
	int top=0;
	int space = 0;
				for (int i=0;i<len;i++) {if (Isnum (A[i])) {if (space) {printf ("");
			Space = 0;
		} printf ("%c", A[i]); } else if (Zhengfu (A[i]) && (i?!
					Isnum (a[i-1]) &&a[i-1]!= ': 1) {//If not operator, direct output if (a[i]== '-') {//output minus sign if (space) {printf ("");
				space=0;
			} printf ("%c", A[i]); }} else{if (top) {if (a[i]==') ' (top--) {if (stack[top]== ' (') break;
				   printf ("%c", Stack[top]);
						} else{while (top) {if (compare (Stack[top-1],a[i])) {printf ("%c", Stack[--top]);
					} else break;
				} Stack[top++]=a[i];
			}} else stack[top++]=a[i];
			 	for (int j=0;j<top;j++) if (stack[j]!= ' (') {space = 1;
			 Break
	}}} while (top) {printf ("%c", Stack[--top]); }
}