View Compilation Error

0_0_20185267_19296.cpp:2:1: error: 'vector' does not name a type
 vector<int> GetRank(string sample) {
 ^
0_0_20185267_19296.cpp:18:1: error: 'string' does not name a type
 string encode(string s, string sample) {
 ^
0_0_20185267_19296.cpp:35:1: error: 'string' does not name a type
 string decode(string s, string sample) {
 ^