Improve parsing of invalid floats

1 files changed, 15 insertions, 1 deletions

diff --git a/stddev.cpp b/stddev.cpp
index ee36af4..5920b6d 100644
--- a/stddev.cpp
+++ b/stddev.cpp
@@ -1,6 +1,7 @@
 #include <iostream>
 #include <vector>
 #include <cmath>
+#include <cctype>
 
 using namespace std;
 
@@ -17,11 +18,24 @@ int main(int,char **argv){
 
 	vector<double> data;
 
+	bool warned=false;
+
 	double total=0;
+	string word;
 	while(true){
+		cin>>word;
 		double v;
-		cin>>v;
 		if(!cin)break;
+		const char *start=word.c_str();
+		char *endp;
+		v=strtod(start,&endp);
+		if(endp!=start+word.size()||!isfinite(v)){
+			if(!warned){
+				warned=true;
+				cerr<<"Warning: invalid floating-point values detected"<<endl;
+			}
+			continue;
+		}
 		data.push_back(v);
 		total+=v;
 	}