Raw Struct Race · Identity construct versus inline pair

#include <inttypes.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
typedef struct { int32_t x; int32_t y; } Pair;
int main(int argc, char **argv) {
    int32_t n = argc > 1 ? (int32_t)atoi(argv[1]) : 40000000;
    int32_t acc = 0;
    for (int32_t i = 0; i < n; i++) {
        Pair pair = (Pair){i, i + 1};
        acc = (acc + pair.x + pair.y) % 1000003;
    }
    printf("%" PRId32 "\n", acc);
}

construct Pair {
    let x: Int
    let y: Int
}

@main {
    let n: Int(40000000)
    state i: Int(0)
    state acc: Int(0)
    while i < n {
        let pair: Pair(x: i, y: i + 1)
        acc: (acc + pair.x + pair.y) % 1000003
        i: i + 1
    }
    return acc % 251
}