Problem 618

Numbers with given prime factor sum: knapsack over primes to F_24. d[i] counts numbers whose prime factor sum is i, modulo 1e9. Sum d[F_k] for Fibonacci numbers F_k up to 46368.

Answer634212216
Output634212216
StatusPASS
Native helperno
Runtime150 ms
Peak memory1568 KB
Time complexityO(n^2) (estimated)
Space complexityO(n) (estimated)

Performance comparison

MetricOur solutionBest known
Time complexityO(n^2)O(sqrt(n))
Space complexityO(n)O(1)
ApproachFlow solutionTrial division or Pollard rho
VerdictSuboptimal

Flow source

# Project Euler 618
# Numbers with given prime factor sum: knapsack over primes to F_24.
# d[i] counts numbers whose prime factor sum is i, modulo 1e9.
# Sum d[F_k] for Fibonacci numbers F_k up to 46368.

extern {
    function calloc(n: i64, size: i64) -> ptr<void>
    function free(p: ptr<void>) -> void
}

const LIMIT: i64 = 46368
const MOD: i64 = 1000000000

function main() -> i32 {
    let prime: ptr<i8> = calloc(LIMIT + 1, 1)
    let d: ptr<i64> = calloc(LIMIT + 1, 8)
    if prime == null || d == null {
        return 1
    }
    let mut i: i64 = 0
    while i <= LIMIT {
        prime[i] = 1
        i = i + 1
    }
    prime[0] = 0
    prime[1] = 0
    let mut j: i64 = 2
    while j * j <= LIMIT {
        if prime[j] == 1 {
            let mut m: i64 = j * j
            while m <= LIMIT {
                prime[m] = 0
                m = m + j
            }
        }
        j = j + 1
    }
    d[0] = 1
    let mut p: i64 = 2
    while p <= LIMIT {
        if prime[p] == 1 {
            let mut idx: i64 = p
            while idx <= LIMIT {
                d[idx] = (d[idx] + p * d[idx - p]) % MOD
                idx = idx + 1
            }
        }
        p = p + 1
    }
    let mut total: i64 = 0
    let mut a: i64 = 1
    let mut b: i64 = 2
    while b <= LIMIT {
        total = (total + d[b]) % MOD
        let c: i64 = a + b
        a = b
        b = c
    }
    free(prime as ptr<void>)
    free(d as ptr<void>)
    printf("%lld\n", total)
    return 0
}

Generated C

#include <stdint.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/* Flow runtime helpers */
typedef struct flow_temp_node { struct flow_temp_node* next; } flow_temp_node;
static flow_temp_node* flow_temp_head = NULL;
static int flow_temp_atexit_set = 0;
__attribute__((unused)) static void flow_temp_free_all(void) {
    while (flow_temp_head) {
        flow_temp_node* n = flow_temp_head;
        flow_temp_head = n->next;
        free(n);
    }
}
__attribute__((unused)) static void* flow_temp_alloc(size_t nbytes) {
    flow_temp_node* node = (flow_temp_node*)malloc(sizeof(flow_temp_node) + nbytes);
    if (!node) return NULL;
    node->next = flow_temp_head;
    flow_temp_head = node;
    if (!flow_temp_atexit_set) {
        flow_temp_atexit_set = 1;
        atexit(flow_temp_free_all);
    }
    return (void*)(node + 1);
}
#ifndef FLOW_DIAG
#define FLOW_DIAG(msg) fprintf(stderr, "%s", (msg))
#endif
#ifndef FLOW_LOG
#define FLOW_LOG(fmt, ...) printf(fmt, __VA_ARGS__)
#endif
#ifndef FLOW_LOG_EMPTY
#define FLOW_LOG_EMPTY(fmt) printf(fmt)
#endif
static char* flow_strcat(const char* a, const char* b) {
    size_t la = strlen(a ? a : ""), lb = strlen(b ? b : "");
    char* r = (char*)flow_temp_alloc(la + lb + 1);
    if (!r) return NULL;
    if (la) memcpy(r, a, la);
    if (lb) memcpy(r + la, b, lb);
    r[la + lb] = '\0';
    return r;
}

#define __flow_in_arr(arr, val) __extension__ ({ \
    int _found = 0; \
    size_t _n = sizeof(arr)/sizeof((arr)[0]); \
    for (size_t _i = 0; _i < _n; _i++) { \
        if ((arr)[_i] == (val)) { _found = 1; break; } \
    } _found; })

/* Unified fault handler (MISRA #279) — override with -DFLOW_FAULT_HANDLER=fn */
#ifndef FLOW_FAULT_HANDLER
__attribute__((unused)) static inline void flow_fault_handler(const char* msg) {
    fprintf(stderr, "flow: %s\n", msg ? msg : "fault");
    abort();
#if defined(__GNUC__) || defined(__clang__)
    __builtin_unreachable();
#endif
}
#else
#define flow_fault_handler FLOW_FAULT_HANDLER
#endif
#define flow_div_by_zero_handler() flow_fault_handler("division by zero")
#define flow_shift_ub_handler() flow_fault_handler("invalid shift (amount out of range or left-shift of negative)")

#ifndef FLOW_CHECKED_DIV
#define FLOW_CHECKED_DIV(L, R) (((R) != 0) ? ((L) / (R)) : (flow_div_by_zero_handler(), (L) * 0))
#endif
#ifndef FLOW_CHECKED_MOD
#define FLOW_CHECKED_MOD(L, R) (((R) != 0) ? ((L) % (R)) : (flow_div_by_zero_handler(), (L) * 0))
#endif
#ifndef FLOW_CHECKED_SHL
#define FLOW_CHECKED_SHL(L, R) ((((R) >= 0) && ((unsigned long long)(R) < (sizeof(L) * 8ull)) && ((L) >= 0)) ? ((L) << (R)) : (flow_shift_ub_handler(), (L) * 0))
#endif
#ifndef FLOW_CHECKED_SHR
#define FLOW_CHECKED_SHR(L, R) ((((R) >= 0) && ((unsigned long long)(R) < (sizeof(L) * 8ull))) ? ((L) >> (R)) : (flow_shift_ub_handler(), (L) * 0))
#endif

#include <math.h>

void* _ui_state = NULL;

static inline float i32_to_f32(int32_t v) { return (float)v; }

/* Host stub for @gpu kernels (device codegen replaces this). */
static inline int32_t gpu_thread_id(void) { return 0; }

int32_t main(void);

static const int64_t LIMIT = 46368;
static const int64_t MOD = 1000000000;



int32_t main(void) {
    int8_t* prime = (int8_t*)(calloc((LIMIT + 1), 1));
    int64_t* d = (int64_t*)(calloc((LIMIT + 1), 8));
    if ((prime == NULL || d == NULL)) {
        return 1;
    }
    int64_t i = 0;
    while (i <= LIMIT) {
        prime[i] = 1;
        i = (i + 1);
    }
    prime[0] = 0;
    prime[1] = 0;
    int64_t j = 2;
    while ((j * j) <= LIMIT) {
        if (prime[j] == 1) {
            int64_t m = (j * j);
            while (m <= LIMIT) {
                prime[m] = 0;
                m = (m + j);
            }
        }
        j = (j + 1);
    }
    d[0] = 1;
    int64_t p = 2;
    while (p <= LIMIT) {
        if (prime[p] == 1) {
            int64_t idx = p;
            while (idx <= LIMIT) {
                d[idx] = FLOW_CHECKED_MOD(((d[idx] + (p * d[(idx - p)]))), (MOD));
                idx = (idx + 1);
            }
        }
        p = (p + 1);
    }
    int64_t total = 0;
    int64_t a = 1;
    int64_t b = 2;
    while (b <= LIMIT) {
        total = FLOW_CHECKED_MOD(((total + d[b])), (MOD));
        int64_t c = (a + b);
        a = b;
        b = c;
    }
    free(((void*)(prime)));
    free(((void*)(d)));
    printf("%lld\n", total);
    return 0;
}

Generated MLIR

module {
  llvm.func @printf(!llvm.ptr, ...) -> i32
  llvm.mlir.global internal constant @str_0("%lld\n\00") {addr_space = 0 : i32} : !llvm.array<6 x i8>
  func.func private @calloc(i64, i64) -> !llvm.ptr
  func.func private @free(!llvm.ptr) -> ()
  // Constant: LIMIT
  llvm.mlir.global internal constant @LIMIT(46368 : i64) : i64
  // Constant: MOD
  llvm.mlir.global internal constant @MOD(1000000000 : i64) : i64
  func.func @main() -> i32 {
    %1 = llvm.mlir.addressof @LIMIT : !llvm.ptr
    %2 = llvm.load %1 : !llvm.ptr -> i64
    %3 = arith.constant 1 : i32
    %5 = arith.extsi %3 : i32 to i64
    %4 = arith.addi %2, %5 : i64
    %6 = arith.constant 1 : i32
    %7 = arith.extsi %6 : i32 to i64
    %0 = func.call @calloc(%4, %7) : (i64, i64) -> !llvm.ptr
    %9 = llvm.mlir.addressof @LIMIT : !llvm.ptr
    %10 = llvm.load %9 : !llvm.ptr -> i64
    %11 = arith.constant 1 : i32
    %13 = arith.extsi %11 : i32 to i64
    %12 = arith.addi %10, %13 : i64
    %14 = arith.constant 8 : i32
    %15 = arith.extsi %14 : i32 to i64
    %8 = func.call @calloc(%12, %15) : (i64, i64) -> !llvm.ptr
    %16 = llvm.mlir.zero : !llvm.ptr
    %17 = llvm.icmp "eq" %0, %16 : !llvm.ptr
    %18 = scf.if %17 -> (i1) {
      %19 = arith.constant true
      scf.yield %19 : i1
    } else {
      %20 = llvm.mlir.zero : !llvm.ptr
      %21 = llvm.icmp "eq" %8, %20 : !llvm.ptr
      scf.yield %21 : i1
    }
    cf.cond_br %18, ^bb0, ^bb1
    ^bb0:
      %22 = arith.constant 1 : i32
      func.return %22 : i32
    ^bb1:
      cf.br ^bb2
    ^bb2:
    %23 = arith.constant 0 : i32
    %24 = arith.extsi %23 : i32 to i64
    %25 = llvm.mlir.constant(1 : i64) : i64
    %26 = llvm.alloca %25 x i64 : (i64) -> !llvm.ptr
    llvm.store %24, %26 : i64, !llvm.ptr
    cf.br ^bb3
    ^bb3:
    %27 = llvm.load %26 : !llvm.ptr -> i64
    %28 = llvm.mlir.addressof @LIMIT : !llvm.ptr
    %29 = llvm.load %28 : !llvm.ptr -> i64
    %30 = arith.cmpi sle, %27, %29 : i64
    cf.cond_br %30, ^bb4, ^bb5
    ^bb4:
      %31 = arith.constant 1 : i32
      %32 = llvm.load %26 : !llvm.ptr -> i64
      %33 = arith.trunci %31 : i32 to i8
      %34 = llvm.getelementptr %0[%32] : (!llvm.ptr, i64) -> !llvm.ptr, i8
      llvm.store %33, %34 : i8, !llvm.ptr
      %35 = llvm.load %26 : !llvm.ptr -> i64
      %36 = arith.constant 1 : i32
      %38 = arith.extsi %36 : i32 to i64
      %37 = arith.addi %35, %38 : i64
      llvm.store %37, %26 : i64, !llvm.ptr
      cf.br ^bb3
    ^bb5:
    %39 = arith.constant 0 : i32
    %40 = arith.constant 0 : i32
    %41 = arith.trunci %39 : i32 to i8
    %42 = arith.extsi %40 : i32 to i64
    %43 = llvm.getelementptr %0[%42] : (!llvm.ptr, i64) -> !llvm.ptr, i8
    llvm.store %41, %43 : i8, !llvm.ptr
    %44 = arith.constant 0 : i32
    %45 = arith.constant 1 : i32
    %46 = arith.trunci %44 : i32 to i8
    %47 = arith.extsi %45 : i32 to i64
    %48 = llvm.getelementptr %0[%47] : (!llvm.ptr, i64) -> !llvm.ptr, i8
    llvm.store %46, %48 : i8, !llvm.ptr
    %49 = arith.constant 2 : i32
    %50 = arith.extsi %49 : i32 to i64
    %51 = llvm.mlir.constant(1 : i64) : i64
    %52 = llvm.alloca %51 x i64 : (i64) -> !llvm.ptr
    llvm.store %50, %52 : i64, !llvm.ptr
    cf.br ^bb6
    ^bb6:
    %53 = llvm.load %52 : !llvm.ptr -> i64
    %54 = llvm.load %52 : !llvm.ptr -> i64
    %55 = arith.muli %53, %54 : i64
    %56 = llvm.mlir.addressof @LIMIT : !llvm.ptr
    %57 = llvm.load %56 : !llvm.ptr -> i64
    %58 = arith.cmpi sle, %55, %57 : i64
    cf.cond_br %58, ^bb7, ^bb8
    ^bb7:
      %60 = llvm.load %52 : !llvm.ptr -> i64
      %61 = llvm.getelementptr %0[%60] : (!llvm.ptr, i64) -> !llvm.ptr, i8
      %59 = llvm.load %61 : !llvm.ptr -> i8
      %62 = arith.constant 1 : i32
      %64 = arith.extsi %59 : i8 to i32
      %63 = arith.cmpi eq, %64, %62 : i32
      cf.cond_br %63, ^bb9, ^bb10
      ^bb9:
        %65 = llvm.load %52 : !llvm.ptr -> i64
        %66 = llvm.load %52 : !llvm.ptr -> i64
        %67 = arith.muli %65, %66 : i64
        %68 = llvm.mlir.constant(1 : i64) : i64
        %69 = llvm.alloca %68 x i64 : (i64) -> !llvm.ptr
        llvm.store %67, %69 : i64, !llvm.ptr
        cf.br ^bb12
        ^bb12:
        %70 = llvm.load %69 : !llvm.ptr -> i64
        %71 = llvm.mlir.addressof @LIMIT : !llvm.ptr
        %72 = llvm.load %71 : !llvm.ptr -> i64
        %73 = arith.cmpi sle, %70, %72 : i64
        cf.cond_br %73, ^bb13, ^bb14
        ^bb13:
          %74 = arith.constant 0 : i32
          %75 = llvm.load %69 : !llvm.ptr -> i64
          %76 = arith.trunci %74 : i32 to i8
          %77 = llvm.getelementptr %0[%75] : (!llvm.ptr, i64) -> !llvm.ptr, i8
          llvm.store %76, %77 : i8, !llvm.ptr
          %78 = llvm.load %69 : !llvm.ptr -> i64
          %79 = llvm.load %52 : !llvm.ptr -> i64
          %80 = arith.addi %78, %79 : i64
          llvm.store %80, %69 : i64, !llvm.ptr
          cf.br ^bb12
        ^bb14:
        cf.br ^bb11
      ^bb10:
        cf.br ^bb11
      ^bb11:
      %81 = llvm.load %52 : !llvm.ptr -> i64
      %82 = arith.constant 1 : i32
      %84 = arith.extsi %82 : i32 to i64
      %83 = arith.addi %81, %84 : i64
      llvm.store %83, %52 : i64, !llvm.ptr
      cf.br ^bb6
    ^bb8:
    %85 = arith.constant 1 : i32
    %86 = arith.constant 0 : i32
    %87 = arith.extsi %85 : i32 to i64
    %88 = arith.extsi %86 : i32 to i64
    %89 = llvm.getelementptr %8[%88] : (!llvm.ptr, i64) -> !llvm.ptr, i64
    llvm.store %87, %89 : i64, !llvm.ptr
    %90 = arith.constant 2 : i32
    %91 = arith.extsi %90 : i32 to i64
    %92 = llvm.mlir.constant(1 : i64) : i64
    %93 = llvm.alloca %92 x i64 : (i64) -> !llvm.ptr
    llvm.store %91, %93 : i64, !llvm.ptr
    cf.br ^bb15
    ^bb15:
    %94 = llvm.load %93 : !llvm.ptr -> i64
    %95 = llvm.mlir.addressof @LIMIT : !llvm.ptr
    %96 = llvm.load %95 : !llvm.ptr -> i64
    %97 = arith.cmpi sle, %94, %96 : i64
    cf.cond_br %97, ^bb16, ^bb17
    ^bb16:
      %99 = llvm.load %93 : !llvm.ptr -> i64
      %100 = llvm.getelementptr %0[%99] : (!llvm.ptr, i64) -> !llvm.ptr, i8
      %98 = llvm.load %100 : !llvm.ptr -> i8
      %101 = arith.constant 1 : i32
      %103 = arith.extsi %98 : i8 to i32
      %102 = arith.cmpi eq, %103, %101 : i32
      cf.cond_br %102, ^bb18, ^bb19
      ^bb18:
        %104 = llvm.load %93 : !llvm.ptr -> i64
        %105 = llvm.mlir.constant(1 : i64) : i64
        %106 = llvm.alloca %105 x i64 : (i64) -> !llvm.ptr
        llvm.store %104, %106 : i64, !llvm.ptr
        cf.br ^bb21
        ^bb21:
        %107 = llvm.load %106 : !llvm.ptr -> i64
        %108 = llvm.mlir.addressof @LIMIT : !llvm.ptr
        %109 = llvm.load %108 : !llvm.ptr -> i64
        %110 = arith.cmpi sle, %107, %109 : i64
        cf.cond_br %110, ^bb22, ^bb23
        ^bb22:
          %112 = llvm.load %106 : !llvm.ptr -> i64
          %113 = llvm.getelementptr %8[%112] : (!llvm.ptr, i64) -> !llvm.ptr, i64
          %111 = llvm.load %113 : !llvm.ptr -> i64
          %114 = llvm.load %93 : !llvm.ptr -> i64
          %116 = llvm.load %106 : !llvm.ptr -> i64
          %117 = llvm.load %93 : !llvm.ptr -> i64
          %118 = arith.subi %116, %117 : i64
          %119 = llvm.getelementptr %8[%118] : (!llvm.ptr, i64) -> !llvm.ptr, i64
          %115 = llvm.load %119 : !llvm.ptr -> i64
          %120 = arith.muli %114, %115 : i64
          %121 = arith.addi %111, %120 : i64
          %122 = llvm.mlir.addressof @MOD : !llvm.ptr
          %123 = llvm.load %122 : !llvm.ptr -> i64
          %124 = arith.remsi %121, %123 : i64
          %125 = llvm.load %106 : !llvm.ptr -> i64
          %126 = llvm.getelementptr %8[%125] : (!llvm.ptr, i64) -> !llvm.ptr, i64
          llvm.store %124, %126 : i64, !llvm.ptr
          %127 = llvm.load %106 : !llvm.ptr -> i64
          %128 = arith.constant 1 : i32
          %130 = arith.extsi %128 : i32 to i64
          %129 = arith.addi %127, %130 : i64
          llvm.store %129, %106 : i64, !llvm.ptr
          cf.br ^bb21
        ^bb23:
        cf.br ^bb20
      ^bb19:
        cf.br ^bb20
      ^bb20:
      %131 = llvm.load %93 : !llvm.ptr -> i64
      %132 = arith.constant 1 : i32
      %134 = arith.extsi %132 : i32 to i64
      %133 = arith.addi %131, %134 : i64
      llvm.store %133, %93 : i64, !llvm.ptr
      cf.br ^bb15
    ^bb17:
    %135 = arith.constant 0 : i32
    %136 = arith.extsi %135 : i32 to i64
    %137 = llvm.mlir.constant(1 : i64) : i64
    %138 = llvm.alloca %137 x i64 : (i64) -> !llvm.ptr
    llvm.store %136, %138 : i64, !llvm.ptr
    %139 = arith.constant 1 : i32
    %140 = arith.extsi %139 : i32 to i64
    %141 = llvm.mlir.constant(1 : i64) : i64
    %142 = llvm.alloca %141 x i64 : (i64) -> !llvm.ptr
    llvm.store %140, %142 : i64, !llvm.ptr
    %143 = arith.constant 2 : i32
    %144 = arith.extsi %143 : i32 to i64
    %145 = llvm.mlir.constant(1 : i64) : i64
    %146 = llvm.alloca %145 x i64 : (i64) -> !llvm.ptr
    llvm.store %144, %146 : i64, !llvm.ptr
    cf.br ^bb24
    ^bb24:
    %147 = llvm.load %146 : !llvm.ptr -> i64
    %148 = llvm.mlir.addressof @LIMIT : !llvm.ptr
    %149 = llvm.load %148 : !llvm.ptr -> i64
    %150 = arith.cmpi sle, %147, %149 : i64
    cf.cond_br %150, ^bb25, ^bb26
    ^bb25:
      %151 = llvm.load %138 : !llvm.ptr -> i64
      %153 = llvm.load %146 : !llvm.ptr -> i64
      %154 = llvm.getelementptr %8[%153] : (!llvm.ptr, i64) -> !llvm.ptr, i64
      %152 = llvm.load %154 : !llvm.ptr -> i64
      %155 = arith.addi %151, %152 : i64
      %156 = llvm.mlir.addressof @MOD : !llvm.ptr
      %157 = llvm.load %156 : !llvm.ptr -> i64
      %158 = arith.remsi %155, %157 : i64
      llvm.store %158, %138 : i64, !llvm.ptr
      %159 = llvm.load %142 : !llvm.ptr -> i64
      %160 = llvm.load %146 : !llvm.ptr -> i64
      %161 = arith.addi %159, %160 : i64
      %162 = llvm.load %146 : !llvm.ptr -> i64
      llvm.store %162, %142 : i64, !llvm.ptr
      llvm.store %161, %146 : i64, !llvm.ptr
      cf.br ^bb24
    ^bb26:
    func.call @free(%0) : (!llvm.ptr) -> ()
    func.call @free(%8) : (!llvm.ptr) -> ()
    %165 = llvm.mlir.addressof @str_0 : !llvm.ptr
    %166 = llvm.load %138 : !llvm.ptr -> i64
    %167 = llvm.call @printf(%165, %166) vararg(!llvm.func<i32 (ptr, ...)>) : (!llvm.ptr, i64) -> i32
    %168 = arith.constant 0 : i32
    func.return %168 : i32
  }
}