text: Simple Array Sum
  Given an array of N integers, can you find the sum of its elements?
  Input Format
  The first line contains an integer, N, denoting the size of the array.
  The second line contains N space-separated integers representing the array’s elements.
  Output Format
  Print the sum of the array’s elements as a single integer.
  Sample Input
  6
  1 2 3 4 10 11
  Sample Output
  31
  Explanation
  We print the sum of the array’s elements, which is: .
  1+2+3+4+10+11=31
  #include <stdio.h> #include <string.h> #include <math.h> #include <stdlib.h> int main() { int n,i,a,sum=0; scanf("%d",&n); if(n<=1000){ for(i=0;i<n;++i){ scanf("%d",&a); sum=sum+a; } printf("%d",sum); return 0; } }
  Competitive coding
  Hackerrank problem
  According to cs.uic.edu.
  Some texts refer to one-dimensional arrays as vectors, two-dimensional arrays as matrices, and use the general term arrays when the number of dimensions is unspecified or unimportant.
  Declaring Arrays
  Array variables are declared identically to variables of their data type, except that the variable name is followed by one pair of square [ ] brackets for each dimension of the array.
  Uninitialized arrays must have the dimensions of their rows, columns, etc. listed within the square brackets.
  Dimensions used when declaring arrays in C must be positive integral constants or constant expressions.
  In C99, dimensions must still be positive integers, but variables can be used, so long as the variable has a positive value at the time the array is declared. ( Space is allocated only once, at the time the array is declared. The array does NOT change sizes later if the variable used to declare it changes. )
  Examples:
  int i, j, intArray[ 10 ], number;
  float floatArray[ 1000 ];
  int tableArray[ 3 ][ 5 ]; /* 3 rows by 5 columns */
  const int NROWS = 100; // ( Old code would use #define NROWS 100 )
  const int NCOLS = 200; // ( Old code would use #define NCOLS 200 )
  float matrix[ NROWS ][ NCOLS ];
  C99 Only Example:
  int numElements;
  printf( “How big an array do you want? ” );
  scanf( “%d”, &numElements; )
  if( numElements <= 0 ) { printf( "Error - Quitting\n" ); exit( 0 ); } double data[ numElements ]; // This only works in C99, not in plain C For more detail