go-05-lru-cache
0.000
Proposed solution
```go
// solution.go
package challenge
import (
"container/list"
)
type LRUCache[K comparable, V any] struct {
mu sync.Mutex
capacity int
cache map[K]*list.Element
list *list.List
}
func NewLRUCache[K comparable, V any](capacity int) *LRUCache[K, V] {
if capacity <= 0 {
return &LRUCache[K, V]{capacity: 0, cache: make(map[K]*list.Element), list: list.New()}
}
return &LRUCache[K, V]{capacity: capacity, cache: make(map[K]*list.Element), list: list.New()}
}
func (c *LRUCache[K, V]) Get(key K) (V, bool) {
c.mu.Lock()
defer c.mu.Unlock()
if element, found := c.cache[key]; found {
c.list.MoveToFront(element)
return element.Value.(*entry).value, true
}
return V{}, false
}
func (c *LRUCache[K, V]) Put(key K, value V) {
c.mu.Lock()
defer c.mu.Unlock()
if element, found := c.cache[key]; found {
c.list.MoveToFront(element)
element.Value.(*entry).value = value
return
}
if c.Len() == c.capacity {
oldest := c.list.Back()
c.list.Remove(oldest)
delete(c.cache, oldest.Value.(*entry).key)
}
newElement := c.list.PushFront(&entry{key: key, value: value})
c.cache[key] = newElement
}
func (c *LRUCache[K, V]) Len() int {
c.mu.Lock()
defer c.mu.Unlock()
return c.list.Len()
}
type entry struct {
key K
value V
}
func (e *entry) key() K { return e.key }
func (e *entry) value() V { return e.value }
```Test output (stdout)
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"# challenge [challenge.test]\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"./solution.go:9:5: undefined: sync\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"./solution.go:30:9: invalid composite literal type V (no common underlying type)\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"./solution.go:39:3: cannot assign to element.Value.(*entry).value (neither addressable nor a map index expression)\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"./solution.go:60:8: undefined: K\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"./solution.go:61:8: undefined: V\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"./solution.go:64:17: field and method with the same name key\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"\t./solution.go:60:2: other declaration of key\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"./solution.go:64:23: undefined: K\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"./solution.go:65:17: field and method with the same name value\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"\t./solution.go:61:2: other declaration of value\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-output","Output":"./solution.go:65:25: undefined: V\n"}
{"ImportPath":"challenge [challenge.test]","Action":"build-fail"}
{"Time":"2026-06-30T05:53:27.892189951+02:00","Action":"start","Package":"challenge"}
{"Time":"2026-06-30T05:53:27.892243751+02:00","Action":"output","Package":"challenge","Output":"FAIL\tchallenge [build failed]\n"}
{"Time":"2026-06-30T05:53:27.892248391+02:00","Action":"fail","Package":"challenge","Elapsed":0,"FailedBuild":"challenge [challenge.test]"}
Self-repair attempts
[
{
"total": 1,
"answer": "```go\n// solution.go\npackage challenge\n\nimport (\n\t\"container/list\"\n)\n\ntype LRUCache[K comparable, V any] struct {\n\tmu sync.Mutex\n\tcapacity int\n\tcache map[K]*list.Element\n\tlist *list.List\n}\n\nfunc NewLRUCache[K comparable, V any](capacity int) *LRUCache[K, V] {\n\tif capacity <= 0 {\n\t\treturn &LRUCache[K, V]{capacity: 0, cache: make(map[K]*list.Element), list: list.New()}\n\t}\n\treturn &LRUCache[K, V]{capacity: capacity, cache: make(map[K]*list.Element), list: list.New()}\n}\n\nfunc (c *LRUCache[K, V]) Get(key K) (V, bool) {\n\tc.mu.Lock()\n\tdefer c.mu.Unlock()\n\n\tif element, found := c.cache[key]; found {\n\t\tc.list.MoveToFront(element)\n\t\treturn element.Value.(*entry).value, true\n\t}\n\treturn V{}, false\n}\n\nfunc (c *LRUCache[K, V]) Put(key K, value V) {\n\tc.mu.Lock()\n\tdefer c.mu.Unlock()\n\n\tif element, found := c.cache[key]; found {\n\t\tc.list.MoveToFront(element)\n\t\telement.Value.(*entry).value = value\n\t\treturn\n\t}\n\n\tif c.Len() == c.capacity {\n\t\toldest := c.list.Back()\n\t\tc.list.Remove(oldest)\n\t\tdelete(c.cache, oldest.Value.(*entry).key)\n\t}\n\n\tnewElement := c.list.PushFront(&entry{key: key, value: value})\n\tc.cache[key] = newElement\n}\n\nfunc (c *LRUCache[K, V]) Len() int {\n\tc.mu.Lock()\n\tdefer c.mu.Unlock()\n\treturn c.list.Len()\n}\n\ntype entry struct {\n\tkey K\n\tvalue V\n}\n\nfunc (e *entry) key() K { return e.key }\nfunc (e *entry) value() V { return e.value }\n```",
"passed": 0,
"test_error": "{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"# challenge [challenge.test]\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:9:5: undefined: sync\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:30:9: invalid composite literal type V (no common underlying type)\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:39:3: cannot assign to element.Value.(*entry).value (neither addressable nor a map index expression)\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:60:8: undefined: K\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:61:8: undefined: V\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:64:17: field and method with the same name key\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"\\t./solution.go:60:2: other declaration of key\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:64:23: undefined: K\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:65:17: field and method with the same name value\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"\\t./solution.go:61:2: other declaration of value\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:65:25: undefined: V\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-fail\"}\n{\"Time\":\"2026-06-30T05:53:27.892189951+02:00\",\"Action\":\"start\",\"Package\":\"challenge\"}\n{\"Time\":\"2026-06-30T05:53:27.892243751+02:00\",\"Action\":\"output\",\"Package\":\"challenge\",\"Output\":\"FAIL\\tchallenge [build failed]\\n\"}\n{\"Time\":\"2026-06-30T05:53:27.892248391+02:00\",\"Action\":\"fail\",\"Package\":\"challenge\",\"Elapsed\":0,\"FailedBuild\":\"challenge [challenge.test]\"}"
},
{
"total": 1,
"answer": "```go\n// solution.go\npackage challenge\n\nimport (\n\t\"sync\"\n)\n\ntype LRUCache[K comparable, V any] struct {\n\tmu sync.Mutex\n\tcapacity int\n\tcache map[K]*list.Element\n\tlist *list.List\n}\n\nfunc NewLRUCache[K comparable, V any](capacity int) *LRUCache[K, V] {\n\tif capacity <= 0 {\n\t\treturn &LRUCache[K, V]{capacity: 0, cache: make(map[K]*list.Element), list: list.New()}\n\t}\n\treturn &LRUCache[K, V]{capacity: capacity, cache: make(map[K]*list.Element), list: list.New()}\n}\n\nfunc (c *LRUCache[K, V]) Get(key K) (V, bool) {\n\tc.mu.Lock()\n\tdefer c.mu.Unlock()\n\n\tif element, found := c.cache[key]; found {\n\t\tc.list.MoveToFront(element)\n\t\treturn element.Value.(V), true\n\t}\n\treturn V{}, false\n}\n\nfunc (c *LRUCache[K, V]) Put(key K, value V) {\n\tc.mu.Lock()\n\tdefer c.mu.Unlock()\n\n\tif element, found := c.cache[key]; found {\n\t\tc.list.MoveToFront(element)\n\t\telement.Value.(V) = value\n\t\treturn\n\t}\n\n\tif c.Len() == c.capacity {\n\t\toldest := c.list.Back()\n\t\tc.list.Remove(oldest)\n\t\tdelete(c.cache, oldest.Value.(*entry).key)\n\t}\n\n\tnewElement := c.list.PushFront(&entry{key: key, value: value})\n\tc.cache[key] = newElement\n}\n\nfunc (c *LRUCache[K, V]) Len() int {\n\tc.mu.Lock()\n\tdefer c.mu.Unlock()\n\treturn c.list.Len()\n}\n\ntype entry struct {\n\tkey K\n\tvalue V\n}\n\nfunc (e *entry) key() K { return e.key }\nfunc (e *entry) value() V { return e.value }\n```",
"passed": 0,
"test_error": "{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"# challenge [challenge.test]\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:11:15: undefined: list\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:12:9: undefined: list\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:17:58: undefined: list\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:19:64: undefined: list\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:60:8: undefined: K\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:61:8: undefined: V\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:64:17: field and method with the same name key\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"\\t./solution.go:60:2: other declaration of key\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:64:23: undefined: K\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:65:17: field and method with the same name value\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"\\t./solution.go:61:2: other declaration of value\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:65:25: undefined: V\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-output\",\"Output\":\"./solution.go:19:64: too many errors\\n\"}\n{\"ImportPath\":\"challenge [challenge.test]\",\"Action\":\"build-fail\"}\n{\"Time\":\"2026-06-30T05:53:31.548091764+02:00\",\"Action\":\"start\",\"Package\":\"challenge\"}\n{\"Time\":\"2026-06-30T05:53:31.548145295+02:00\",\"Action\":\"output\",\"Package\":\"challenge\",\"Output\":\"FAIL\\tchallenge [build failed]\\n\"}\n{\"Time\":\"2026-06-30T05:53:31.548149275+02:00\",\"Action\":\"fail\",\"Package\":\"challenge\",\"Elapsed\":0,\"FailedBuild\":\"challenge [challenge.test]\"}"
},
{
"total": 1,
"answer": "```go\n// solution.go\npackage challenge\n\nimport (\n\t\"sync\"\n)\n\ntype LRUCache[K comparable, V any] struct {\n\tmu sync.Mutex\n\tcapacity int\n\tcache map[K]*list.Element\n\tlist *list.List\n}\n\nfunc NewLRUCache[K comparable, V any](capacity int) *LRUCache[K, V] {\n\tif capacity <= 0 {\n\t\treturn &LRUCache[K, V]{capacity: 0, cache: make(map[K]*list.Element), list: list.New()}\n\t}\n\treturn &LRUCache[K, V]{capacity: capacity, cache: make(map[K]*list.Element), list: list.New()}\n}\n\nfunc (c *LRUCache[K, V]) Get(key K) (V, bool) {\n\tc.mu.Lock()\n\tdefer c.mu.Unlock()\n\n\tif element, found := c.cache[key]; found {\n\t\tc.list.MoveToFront(element)\n\t\treturn element.Value.(V), true\n\t}\n\treturn V{}, false\n}\n\nfunc (c *LRUCache[K, V]) Put(key K, value V) {\n\tc.mu.Lock()\n\tdefer c.mu.Unlock()\n\n\tif element, found := c.cache[key]; found {\n\t\tc.list.MoveToFront(element)\n\t\telement.Value.(V) = value\n\t\treturn\n\t}\n\n\tif c.Len() == c.capacity {\n\t\toldest := c.list.Back()\n\t\tc.list.Remove(oldest)\n\t\tdelete(c.cache, oldest.Value.(*entry).key)\n\t}\n\n\tnewElement := c.list.PushFront(&entry{key: key, value: value})\n\tc.cache[key] = newElement\n}\n\nfunc (c *LRUCache[K, V]) Len() int {\n\tc.mu.Lock()\n\tdefer c.mu.Unlock()\n\treturn c.list.Len()\n}\n\ntype entry struct {\n\tkey K\n\tvalue V\n}\n\nfunc (e *entry) key() K { return e.key }\nfunc (e *entry) value() V { return e.value }\n```",
"passed": 0,
"test_error": ""
}
]System prompt
You are an expert programmer. Solve the task exactly as specified. Output your solution as fenced code blocks using the required file name(s) and the exact function/type signatures requested. Prefer correctness; do not include prose outside code unless asked.