codeforces Strings of Power

题目链接：http://codeforces.com/problemset/problem/318/B

题目大意：字符串匹配问题。找heavy和metal搭配的总数。

#include<iostream>#include<cstring>#include<string>using namespace std;int main(void){    string str;    int i;    cin>>str;    long long sum1=0, sum2=0;    for(i=0; i<str.size(); ++i)    {        if("heavy"==str.substr(i, 5))           ++sum1;        else if("metal"==str.substr(i, 5))            sum2+=sum1;    }    cout<<sum2<<endl;    return 0;}