PAT A1108

字符串处理，个人觉得最好的办法还是建立一个处理函数统一进行处理；#include<iostream>#include<cstdio>#include<string>using namespace std;const int maxn = 101;bool Judge(string s,double &x){ int dot = 0,n1 = 0,n2 = 0; int i = 0; if(s[i]==’-’) i++; for(;i < s.size();i++){ if(s[i]==’.’){ dot++; if(dot > 1) return 0; } else if(s[i]>=‘0’&&s[i]<=‘9’){ if(dot) n2++; else n1++; } else return 0; } if(n2>2) return 0; sscanf(s.c_str(),"%lf",&x); if(x>=-1000&&x<=1000) return 1; return 0;} int main(){ int n,cnt = 0; double x,ans = 0; string s; cin >> n; for(int i = 0;i < n;i++){ cin >> s; if(Judge(s,x)){ cnt++; ans += x; } else { cout << “ERROR: " << s << " is not a legal number\n”; } } if(cnt==1){ printf(“The average of 1 number is %.2f\n”,ans); return 0; } printf(“The average of %d numbers is “,cnt); if(cnt) printf(”%.2f\n”,ans/cnt); else cout << “Undefined\n”; return 0;}