flowchart TD
    S["16 lanes, keys<br/>2 3 1 3 2 0 0 1 0 1 3 2 2 1 2 2<br/>(value = key)"] --> I0["iteration 0<br/>first active lane has key 2<br/>6 lanes, sum 12"]
    I0 -->|"10 lanes left"| I1["iteration 1<br/>key 3: 3 lanes, sum 9"]
    I1 -->|"7 lanes left"| I2["iteration 2<br/>key 1: 4 lanes, sum 4"]
    I2 -->|"3 lanes left"| I3["iteration 3<br/>key 0: 3 lanes, sum 0"]
    S -.->|"folded break: sum after the loop"| A["all 16 lanes at once<br/>sum 25"]