不考虑优先级的加减乘除

#include <iostream>using namespace std;int main(){char temp[256];cin>>temp;int rst=0;int ad=0;char smb='+';int i=-1;do{i++;if(temp[i]<=47||temp[i]=='\0'){switch (smb){case '+':rst=rst+ad;break;case '-':rst=rst-ad;break;case '*':rst=rst*ad;break;case '/':if (ad==0) {cout<<rst<<endl;return 0;} else {rst=rst/ad;} ;break;default: break;}smb=temp[i];ad=0;}else{int ii=temp[i]-48;ad=ad*10+ii;}}while (temp[i]!='\0');cout<<rst<<endl;return 0;}