相信我 会更快
#include <bits/stdc++.h> using namespace std; int main(int argc, char** argv) { string c2 = "56"; int a = c2[0] - ‘0‘; cout << a<<endl; char c1 = ‘7‘; int b = c1 - ‘0‘; cout << b<<endl; return 0; }
原文：https://www.cnblogs.com/ranzhong/p/14128881.html