Segmentation fault when i get texture from a sprite

I got segmentation fault when i execute this code:

void HelloWorld::loadCharacter(cocos2d::Size winS){
_spriteCache = SpriteFrameCache::getInstance();
for (int i = 1; i < 14; i++)
    std::string num = StringUtils::format("%d", i);
    Sprite *sprite = Sprite::create("head"+num+".tiff");
    SpriteFrame *spriteFrame = SpriteFrame::createWithTexture(sprite->getTexture(),sprite->getTextureRect());
_idleAnimation = Animation::createWithSpriteFrames(_idlePlayer, 0.05f);
auto temp_sprite = Sprite::create();
temp_sprite->setPosition(Vec2(winS.width * 0.2, winS.height * 0.5));
auto walk = Animate::create(_idleAnimation);


What is num?

Is a iterator, but this is not the problem.

Its crashes when i call sprite->getTexture() and sprite->getTextureRect()

Here is one way to do it. A loop works great too

I try create a SpriteFrame with a Sprite, passing the texture and rect.

I dont think .tiff format is supported, you should use png or jpg.
First try with single file first.