Loops

Loops

C has three loop constructs: for, while, and do-while.

for Loop

The most common loop. It has three parts: initialization, condition, and update:

for (int i = 0; i < 5; i++) {
    printf("%d\n", i);
}

"Captain, we appear to be caught in a temporal causality loop." -- The Enterprise keeps reliving the same moment (TNG S5E18). At least they had a break condition.

while Loop

Repeats while a condition is true:

int i = 0;
while (i < 5) {
    printf("%d\n", i);
    i++;
}

do-while Loop

Executes the body at least once, then checks the condition:

int i = 0;
do {
    printf("%d\n", i);
    i++;
} while (i < 5);

break and continue

• break -- exits the loop immediately
• continue -- skips to the next iteration

for (int i = 0; i < 10; i++) {
    if (i == 5) break;       // stops at 5
    if (i % 2 == 0) continue; // skip even numbers
    printf("%d\n", i);       // prints 1, 3
}

Your Task

Write a function int sum_range(int a, int b) that returns the sum of all integers from a to b (inclusive). For example, sum_range(1, 5) returns 15. Print the result of sum_range(1, 10).