Code:The code: #include<stdio.h> #include<stdlib.h> #define MaxSize 50 char postexp[MaxSize]; typedef struct{ char elem[MaxSize]; int top;}SqStack; void InitStack(SqStack *&s) {s=(SqStack *)malloc(sizeof(SqStack)); s->top=-1;} int push(SqStack *&s,char e) {if(s->top==MaxSize-1) return 0; s->top++; s->elem[s->top]=e; return 1;} void trans(char *exp) {SqStack *s;int i=0; while(*exp!='\0') {switch(*exp) {case '(':push(s,*exp);exp++;break; case ')':while(s->elem[s->top]!='(') {postexp[i++]=s->elem[s->top]; s->top--;} s->top--;exp++;break; case '*': case '/':if(s->elem[s->top]=='*'||s->elem[s->top]=='/') postexp[i++]=s->elem[s->top]; s->top--;push(s,*exp);exp++;break; case '+': case '-':while(s->top!=-1&&s->elem[s->top]!='(') {postexp[i++]=s->elem[s->top];s->top--;} push(s,*exp);exp++;break; case ' ':exp++;break; default:while(*exp>='0'&&*exp<='9') {postexp[i++]=*exp;exp++;} postexp[i++]='#';}} while(s->top!=-1) {postexp[i++]=s->elem[s->top]; s->top--;} postexp[i]='\0'; } void main() {SqStack *s;char exp[]="2+3*4/(5+6)"; InitStack(s); trans(exp,postexp); gets(postexp); } Compile with VC seems OK but the running process throws exception, and debug information as follows: Loaded symbols for 'H:\Visual C++ 6.0\新建文件夹\MSDev98\MyProjects\EXP\Debug\EXP.exe' Loaded 'C:\WINDOWS\system32\ntdll.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\kernel32.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\version.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\msvcrt.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\advapi32.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\rpcrt4.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\secur32.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\user32.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\gdi32.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\shlwapi.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\imm32.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\lpk.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\usp10.dll', no matching symbolic information found. Loaded 'C:\WINDOWS\system32\apphelp.dll', no matching symbolic information found. The thread 0xF08 has exited with code 0 (0x0). How dizzy I am to find out the problem .Any friend can help me?