#include <iostream.h> struct list {     int index;     int a;     char b; }; struct list s[100]; int comp1(char a,char b) {     char op[4][2]={'*','/','+','-','(','(',')',')'};     int i;     int a1,b1;     for(i=0;i<4;i++)     if (a==op[i][0] || a==op[i][1])     {         a1=i;         break;     }     for(i=0;i<4;i++)     if (b==op[i][0] || b==op[i][1])     {         b1=i;         break;     }     if (a1<b1) return 1;     else return 0; } int comp2(char a,char b) {     char op[4][2]={'(','(','*','/','+','-',')',')'};     int i;     int a1,b1;     for(i=0;i<4;i++)     if (a==op[i][0] || a==op[i][1])     {         a1=i;         break;     }     for(i=0;i<4;i++)     if (b==op[i][0] || b==op[i][1])     {         b1=i;         break;     }     if (a1<b1) return 1;     else return 0; } int oper(int a,int b,char op) {     int result;     if(op=='*') result=a*b;     else if(op=='/') result=a/b;     else if(op=='+') result=a+b;     else if(op=='-') result=a-b;     return result; } int main() {     int len=0,i=0;     int number=0;     char enter[100];     cin>>enter;     while(enter[i]!='\0')     {         if(enter[i]>='0' && enter[i]<='9')         {             if (enter[i+1]>='0' && enter[i+1]<='9')                 number=10*number+enter[i]-'0';             else             {             s[len].index=1;             s[len].a=10*number+enter[i]-'0';             s[len].b='0';             len++;             number=0;             }         }         else         {             s[len].index=0;             s[len].a=0;             s[len].b=enter[i];             len++;         }             i++;     }     /*for (i=0;i<len;i++)     {         if (s[i].index)         cout<<s[i].index<<" "<<s[i].a<<endl;         else         cout<<s[i].index<<" "<<s[i].b<<endl;     }*/     int s1[100],top1=0,top2=0;     char s2[100];     s2[top2]='(';top2++;     for(i=0;i<len;i++)     {         if (s[i].b=='=')         {             while(top1!=0)             {             int m=s1[top1-1];             top1--;             int n=s1[top1-1];             top1--;             char op=s2[top2-1];             top2--;             int result=oper(n,m,op);             s1[top1]=result;             top1++;             }         }         if(s[i].index==1)         {             s1[top1]=s[i].a;             top1++;         }         else         {             if (comp1(s[i].b,s2[top2-1])==1)             {                 s2[top2]=s[i].b;                 top2++;             }             else             {                 while(comp2(s[i].b,s2[top2-1])==0)                 {                     int m=s1[top1-1];                     top1--;                     int n=s1[top1-1];                     top1--;                     char op=s2[top2-1];                     top2--;                     int result=oper(n,m,op);                     s1[top1]=result;                     top1++;                 }             }         }     }     //cout<<s1[0]<<endl;     /*char a,b;     while(cin>>a>>b)     {         cout<<comp1(a,b)<<" "<<comp2(a,b)<<endl;     }     */ }

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