Problem Statement
You are given time in AM/PM format. Can you convert this into a 24-hour format?
Input
Input consists of time in the AM/PM format i.e. hh:mm:ssAM or hh:mm:ssPM
where 01≤hh≤12.
Sample: 07:05:45PM
Output
You need to print the time in a 24-hour format i.e. hh:mm:ss
where 00≤hh≤23.
Sample output for the above input: 19:05:45
Note: Midnight is 12:00:00AM or 00:00:00. Noon is 12:00:00PM.
#include <cmath> #include <cstdio> #include <vector> #include <iostream> #include <algorithm> using namespace std; int main() { /* Enter your code here. Read input from STDIN. Print output to STDOUT */ string time=""; cin>>time; if(time[time.size()-2]==‘A‘){ if(time.substr(0,2)=="12") cout<<"00"<<time.substr(2,time.size()-4)<<endl; else cout<<time.substr(0,time.size()-2)<<endl; } if(time[time.size()-2]==‘P‘){ if(time.substr(0,2)=="12") cout<<time.substr(0,time.size()-2)<<endl; else cout<<to_string(stoi(time.substr(0,2))+12)<<time.substr(2,time.size()-4)<<endl; } return 0; }
原文：http://www.cnblogs.com/XingyingLiu/p/4946879.html