STL Cheat Sheet
Creation
•Make an empty vector of integers.
vector< int > iseq1;
•Make a 10-element vector of doubles, each initialized to -1.
vector< double > iseq2( 10, -1 );
•A value that is a 10-element vector of ints, each initialized to 50.
vector< double >( 10, 50 );
•Make a string, integer pair initialized to “up”, 15.
pair< string, int > myPair( "up", 15 );
•A value that is a double, integer pair containing 3.14, 7.
pair< double, int >( 3.14, 7 ); // Types given explicitly
make_pair( 3.14, 7 ); // Types inferred by the compiler.
•Make a 100-element vector of string, double pairs, each initialized to “height”, -1.
vector< pair< string, double > > pseq( 100, make_pair( string("height"), -1.0 ) );
•Make an empty vector of vectors of ints.
vector< vector< int > > matrix1;
•Make a 10 ×20 vector of vectors of ints, each element initialized to 3.
vector< vector< int > > matrix2( 10, vector< int >( 20, 3 ) );
•Make an iterator that can point to an element of a vector of ints.
vector< int >::iterator pos;
Access and Modification
•Number of items in a vector (typically unsigned int)
iseq1.size()
•Number of rows in a vector of vectors.
matrix2.size()
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