 A collection of variables having the same data type
 The variables are thought as being structured in two dimensions
 Each variable is accessed using:
(i) a name which is the same for all of them
(ii) a pair of indices that represent the position of the variable in each dimension
 In other words, a twodimensional array is an array of arrays !!
 Specify the type of the variables followed by the size in each dimension
DataType ArrayName [ConstIntExpression][ConstIntExpression]

ArrayName [IndexExpression][IndexExpression]

 The IndexExpression may be just a constant, or a variable or even an expression
 The result of IndexExpression must be an integer value
 Examples: value[4][1], value[2*a+1][a1] (assuming a is an integer)
 Assign a value: value[2][3]=100;
 Read a value into it: cin >> value[2][3];
 Write its contents: cout << value[2][3];
 Pass it as a parameter: y=sqrt[value[2][3]);
 Twodimensional arrays can be initialized in a declaration
int value[2][3] = { {10, 20, 12} {13, 33, 45} };
 Twodimensional arrays can also be initialized using two loop statements:
 No aggregate operations (assignment, comparison, arithmetic, etc.)
 Passing a twodimensional array to a function ? Yes !!
 Sum the rows
 Sum the columns
 Sum all the elements
 Print the table
 Compute the average temperature per week
for(i=0; i<52; i++) { sum = 0.0; for(j=0; j<7; j++) sum = sum + temperature[i][j]; average = sum / 7; cout << "The average temperature of the " << i << "th week is " << average << endl; }
 Compute the average temperature for each day of the week
for(j=0; j<7; j++) { sum = 0.0; for(i=0; i<52; i++) sum = sum + temperature[i][j]; average = sum / 52; cout << "The average temperature of the " << j << "th day is " << average << endl; }
 Compute the average temperature of the year
sum = 0.0; for(i=0; i<52; i++) for(j=0; j<7; j++) sum = sum + temperature[i][j]; average = sum / (7*52); cout << "The average temperature of the year is " << average << endl; }
 Week by week
for(i=0; i<52; i++) { for(j=0; j<7; j++) cout << temperature[i][j] << " "; cout << endl; }
for(j=0; j<7; j++) { for(i=0; i<52; i++) cout << temperature[i][j] << " "; cout << endl; }