Sum Array Values
An accumulator reduces a sequence to one total.
What is Sum Array Values?
An accumulator reduces a sequence to one total.
Calculate the sum of all values in an array.
Important points
- Compile with warnings enabled and fix every warning.
- Know the lifetime and type of every value.
- Validate input and keep array bounds explicit.
C and C++ code examples
main.c
#include <stdio.h>
int main(void) {
int values[] = {2, 4, 6, 8, 10}; int total = 0;
// sizeof determines the local array length.
for (size_t i = 0; i < sizeof values / sizeof values[0]; ++i) total += values[i];
printf("sum=%d\n", total);
}
sum=30C++
main.cpp
#include <iostream>
#include <numeric>
#include <vector>
int main() {
std::vector values{2, 4, 6, 8, 10};
// accumulate folds the range into one total.
std::cout << "sum=" << std::accumulate(values.begin(), values.end(), 0) << '\n';
}
sum=30C and C++ comparison
Initialize the total to zero and add every element exactly once.
C
C exposes small procedural APIs and makes representation details explicit.
C++
C++ retains the low-level model while adding safer library types and abstractions.
Practice exercises
Run both versions, then modify them to observe the different language guarantees.
- Add invalid and boundary-value inputs.
- Compile with -Wall -Wextra -Wpedantic.
- Move reusable declarations into a header and implementation file.